[python] Add convenience methods

5 files changed, 2586 insertions, 593 deletions

diff --git a/python/src/_cdec.cpp b/python/src/_cdec.cpp
index 948d99b6..3a127ba9 100644
--- a/python/src/_cdec.cpp
+++ b/python/src/_cdec.cpp
@@ -1,4 +1,4 @@
-/* Generated by Cython 0.16 on Thu Jul  5 13:43:06 2012 */
+/* Generated by Cython 0.16 on Thu Jul  5 16:20:15 2012 */
 
 #define PY_SSIZE_T_CLEAN
 #include "Python.h"
@@ -402,11 +402,13 @@ struct __pyx_obj_5_cdec_Lattice;
 struct __pyx_obj_5_cdec___pyx_scope_struct____iter__;
 struct __pyx_obj_5_cdec___pyx_scope_struct_2_kbest;
 struct __pyx_obj_5_cdec_Candidate;
+struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines;
 struct __pyx_obj_5_cdec___pyx_scope_struct_5_sample;
 struct __pyx_obj_5_cdec_DenseVector;
 struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__;
-struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__;
-struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__;
+struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot;
 struct __pyx_opt_args_5_cdec_as_str;
 
 /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":3
@@ -421,7 +423,7 @@ struct __pyx_opt_args_5_cdec_as_str {
   PyObject *error_msg;
 };
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":111
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":122
  *         return CandidateSet(self)
  * 
  * cdef class Scorer:             # <<<<<<<<<<<<<<
@@ -434,7 +436,7 @@ struct __pyx_obj_5_cdec_Scorer {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":59
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":70
  *         return result
  * 
  * cdef class CandidateSet:             # <<<<<<<<<<<<<<
@@ -449,7 +451,7 @@ struct __pyx_obj_5_cdec_CandidateSet {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":27
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":36
  *             return fmap
  * 
  * cdef class SufficientStats:             # <<<<<<<<<<<<<<
@@ -525,7 +527,7 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_3_kbest_tree {
  * 
  * cdef class Decoder:             # <<<<<<<<<<<<<<
  *     cdef decoder.Decoder* dec
- *     cdef public DenseVector weights
+ *     cdef DenseVector weights
  */
 struct __pyx_obj_5_cdec_Decoder {
   PyObject_HEAD
@@ -534,7 +536,7 @@ struct __pyx_obj_5_cdec_Decoder {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":92
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":103
  *         self.cs.AddKBestCandidates(hypergraph.hg[0], k, self.scorer.get())
  * 
  * cdef class SegmentEvaluator:             # <<<<<<<<<<<<<<
@@ -624,8 +626,8 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_2_kbest {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":13
- *     return ret
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":22
+ *         return stats
  * 
  * cdef class Candidate:             # <<<<<<<<<<<<<<
  *     cdef mteval.Candidate* candidate
@@ -638,6 +640,29 @@ struct __pyx_obj_5_cdec_Candidate {
 };
 
 
+/* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":59
+ * 
+ *     def todot(self):
+ *         def lines():             # <<<<<<<<<<<<<<
+ *             yield 'digraph lattice {'
+ *             yield 'rankdir = LR;'
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines {
+  PyObject_HEAD
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *__pyx_outer_scope;
+  PyObject *__pyx_v_delta;
+  PyObject *__pyx_v_i;
+  PyObject *__pyx_v_label;
+  PyObject *__pyx_v_weight;
+  Py_ssize_t __pyx_t_0;
+  PyObject *__pyx_t_1;
+  PyObject *(*__pyx_t_2)(PyObject *);
+  PyObject *__pyx_t_3;
+  Py_ssize_t __pyx_t_4;
+  PyObject *(*__pyx_t_5)(PyObject *);
+};
+
+
 /* "/Users/vchahun/Sandbox/cdec/python/src/hypergraph.pxi":75
  *             del derivations
  * 
@@ -686,14 +711,31 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_6___iter__ {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":84
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":54
+ *         return self.stats.size()
+ * 
+ *     def __iter__(self):             # <<<<<<<<<<<<<<
+ *         for i in range(len(self)):
+ *             yield self.stats[0][i]
+ */
+struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ {
+  PyObject_HEAD
+  PyObject *__pyx_v_i;
+  struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self;
+  Py_ssize_t __pyx_t_0;
+  PyObject *__pyx_t_1;
+  PyObject *(*__pyx_t_2)(PyObject *);
+};
+
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":95
  *         return candidate
  * 
  *     def __iter__(self):             # <<<<<<<<<<<<<<
  *         cdef unsigned i
  *         for i in range(len(self)):
  */
-struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ {
+struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ {
   PyObject_HEAD
   unsigned int __pyx_v_i;
   struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self;
@@ -702,20 +744,16 @@ struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ {
 };
 
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":45
- *         return self.stats.size()
+/* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":58
+ *         del self.lattice
  * 
- *     def __iter__(self):             # <<<<<<<<<<<<<<
- *         for i in range(len(self)):
- *             yield self.stats[0][i]
+ *     def todot(self):             # <<<<<<<<<<<<<<
+ *         def lines():
+ *             yield 'digraph lattice {'
  */
-struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ {
+struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot {
   PyObject_HEAD
-  PyObject *__pyx_v_i;
-  struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self;
-  Py_ssize_t __pyx_t_0;
-  PyObject *__pyx_t_1;
-  PyObject *(*__pyx_t_2)(PyObject *);
+  struct __pyx_obj_5_cdec_Lattice *__pyx_v_self;
 };
 
 #ifndef CYTHON_REFNANNY
@@ -878,6 +916,8 @@ static CYTHON_INLINE PyObject *__Pyx_GetItemInt_Fast(PyObject *o, Py_ssize_t i)
     return __Pyx_GetItemInt_Generic(o, PyInt_FromSsize_t(i));
 }
 
+static CYTHON_INLINE void __Pyx_RaiseClosureNameError(const char *varname);
+
 static double __Pyx__PyObject_AsDouble(PyObject* obj); /* proto */
 #define __Pyx_PyObject_AsDouble(obj) \
 ((likely(PyFloat_CheckExact(obj))) ? \
@@ -895,6 +935,48 @@ static PyObject *__Pyx_CreateClass(PyObject *bases, PyObject *dict, PyObject *na
 
 static PyObject* __Pyx_Globals(void); /*proto*/
 
+#define __Pyx_CyFunction_USED 1
+#include <structmember.h>
+#define __Pyx_CYFUNCTION_STATICMETHOD  0x01
+#define __Pyx_CYFUNCTION_CLASSMETHOD   0x02
+#define __Pyx_CYFUNCTION_CCLASS        0x04
+#define __Pyx_CyFunction_GetClosure(f) \
+    (((__pyx_CyFunctionObject *) (f))->func_closure)
+#define __Pyx_CyFunction_GetClassObj(f) \
+    (((__pyx_CyFunctionObject *) (f))->func_classobj)
+#define __Pyx_CyFunction_Defaults(type, f) \
+    ((type *)(((__pyx_CyFunctionObject *) (f))->defaults))
+#define __Pyx_CyFunction_SetDefaultsGetter(f, g) \
+    ((__pyx_CyFunctionObject *) (f))->defaults_getter = (g)
+typedef struct {
+    PyCFunctionObject func;
+    int flags;
+    PyObject *func_dict;
+    PyObject *func_weakreflist;
+    PyObject *func_name;
+    PyObject *func_doc;
+    PyObject *func_code;
+    PyObject *func_closure;
+    PyObject *func_classobj; /* No-args super() class cell */
+    void *defaults;
+    int defaults_pyobjects;
+    PyObject *defaults_tuple; /* Const defaults tuple */
+    PyObject *(*defaults_getter)(PyObject *);
+} __pyx_CyFunctionObject;
+static PyTypeObject *__pyx_CyFunctionType = 0;
+#define __Pyx_CyFunction_NewEx(ml, flags, self, module, code) \
+    __Pyx_CyFunction_New(__pyx_CyFunctionType, ml, flags, self, module, code)
+static PyObject *__Pyx_CyFunction_New(PyTypeObject *,
+                                      PyMethodDef *ml, int flags,
+                                      PyObject *self, PyObject *module,
+                                      PyObject* code);
+static CYTHON_INLINE void *__Pyx_CyFunction_InitDefaults(PyObject *m,
+                                                         size_t size,
+                                                         int pyobjects);
+static CYTHON_INLINE void __Pyx_CyFunction_SetDefaultsTuple(PyObject *m,
+                                                            PyObject *tuple);
+static int __Pyx_CyFunction_init(void);
+
 static CYTHON_INLINE unsigned char __Pyx_PyInt_AsUnsignedChar(PyObject *);
 
 static CYTHON_INLINE unsigned short __Pyx_PyInt_AsUnsignedShort(PyObject *);
@@ -1011,9 +1093,12 @@ static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_3_kbest_tree = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_4_kbest_features = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_5_sample = 0;
 static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_6___iter__ = 0;
-static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_7___iter__ = 0;
-static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_8___iter__ = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_7_todot = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_8_lines = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_9___iter__ = 0;
+static PyTypeObject *__pyx_ptype_5_cdec___pyx_scope_struct_10___iter__ = 0;
 static char *__pyx_f_5_cdec_as_str(PyObject *, struct __pyx_opt_args_5_cdec_as_str *__pyx_optional_args); /*proto*/
+static struct __pyx_obj_5_cdec_SufficientStats *__pyx_f_5_cdec_as_stats(PyObject *, PyObject *); /*proto*/
 #define __Pyx_MODULE_NAME "_cdec"
 int __pyx_module_is_main__cdec = 0;
 
@@ -1042,17 +1127,18 @@ static PyObject *__pyx_pf_5_cdec_12SparseVector_11dot(struct __pyx_obj_5_cdec_Sp
 static PyObject *__pyx_pf_5_cdec_12SparseVector_13__richcmp__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y, int __pyx_v_op); /* proto */
 static Py_ssize_t __pyx_pf_5_cdec_12SparseVector_15__len__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
 static int __pyx_pf_5_cdec_12SparseVector_17__contains__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, char *__pyx_v_fname); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_19__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_21__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_23__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_19__neg__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_21__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_23__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_25__imul__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
 #if PY_MAJOR_VERSION < 3
-static PyObject *__pyx_pf_5_cdec_12SparseVector_25__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_27__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar); /* proto */
 #endif
-static PyObject *__pyx_pf_5_cdec_12SparseVector_27__add__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_29__sub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
-static PyObject *__pyx_pf_5_cdec_12SparseVector_31__mul__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_29__add__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_31__sub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_33__mul__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
 #if PY_MAJOR_VERSION < 3
-static PyObject *__pyx_pf_5_cdec_12SparseVector_33__div__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_12SparseVector_35__div__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
 #endif
 static void __pyx_pf_5_cdec_10Hypergraph___dealloc__(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_10Hypergraph_2viterbi(struct __pyx_obj_5_cdec_Hypergraph *__pyx_v_self); /* proto */
@@ -1074,6 +1160,8 @@ static Py_ssize_t __pyx_pf_5_cdec_7Lattice_6__len__(struct __pyx_obj_5_cdec_Latt
 static PyObject *__pyx_pf_5_cdec_7Lattice_8__str__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Lattice_10__iter__(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
 static void __pyx_pf_5_cdec_7Lattice_13__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_7Lattice_5todot_lines(PyObject *__pyx_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_7Lattice_15todot(struct __pyx_obj_5_cdec_Lattice *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_9Candidate_5words___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_9Candidate_4fmap___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_9Candidate_5score___get__(struct __pyx_obj_5_cdec_Candidate *__pyx_v_self); /* proto */
@@ -1084,7 +1172,7 @@ static PyObject *__pyx_pf_5_cdec_15SufficientStats_6detail___get__(struct __pyx_
 static Py_ssize_t __pyx_pf_5_cdec_15SufficientStats_2__len__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_15SufficientStats_4__iter__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_5_cdec_15SufficientStats_7__iadd__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_self, struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_other); /* proto */
-static PyObject *__pyx_pf_5_cdec_15SufficientStats_9__add__(struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_x, struct __pyx_obj_5_cdec_SufficientStats *__pyx_v_y); /* proto */
+static PyObject *__pyx_pf_5_cdec_15SufficientStats_9__add__(PyObject *__pyx_v_x, PyObject *__pyx_v_y); /* proto */
 static int __pyx_pf_5_cdec_12CandidateSet___cinit__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self, struct __pyx_obj_5_cdec_SegmentEvaluator *__pyx_v_evaluator); /* proto */
 static void __pyx_pf_5_cdec_12CandidateSet_2__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self); /* proto */
 static Py_ssize_t __pyx_pf_5_cdec_12CandidateSet_4__len__(struct __pyx_obj_5_cdec_CandidateSet *__pyx_v_self); /* proto */
@@ -1100,20 +1188,31 @@ static PyObject *__pyx_pf_5_cdec_6Scorer_4__call__(struct __pyx_obj_5_cdec_Score
 static PyObject *__pyx_pf_5_cdec_6Scorer_6__str__(struct __pyx_obj_5_cdec_Scorer *__pyx_v_self); /* proto */
 static int __pyx_pf_5_cdec_7Decoder___cinit__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, char *__pyx_v_config); /* proto */
 static void __pyx_pf_5_cdec_7Decoder_2__dealloc__(CYTHON_UNUSED struct __pyx_obj_5_cdec_Decoder *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_5_cdec_7Decoder_7weights___get__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self); /* proto */
+static int __pyx_pf_5_cdec_7Decoder_7weights_2__set__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_weights); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Decoder_4read_weights(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_cfg); /* proto */
 static PyObject *__pyx_pf_5_cdec_7Decoder_6translate(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_sentence, PyObject *__pyx_v_grammar); /* proto */
-static PyObject *__pyx_pf_5_cdec_7Decoder_7weights___get__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self); /* proto */
-static int __pyx_pf_5_cdec_7Decoder_7weights_2__set__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_value); /* proto */
-static int __pyx_pf_5_cdec_7Decoder_7weights_4__del__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self); /* proto */
 static char __pyx_k_1[] = "cannot take the dot product of %s and SparseVector";
 static char __pyx_k_2[] = "comparison not implemented for SparseVector";
 static char __pyx_k_10[] = "csplit_preserve_full_word";
 static char __pyx_k_11[] = "cannot reweight hypergraph with %s";
 static char __pyx_k_13[] = "Cannot create lattice from %s";
 static char __pyx_k_14[] = "lattice index out of range";
-static char __pyx_k_19[] = "Cannot convert type %s to str";
-static char __pyx_k_21[] = "candidate set index out of range";
-static char __pyx_k_25[] = "Cannot translate input type %s";
+static char __pyx_k_19[] = "digraph lattice {";
+  static char __pyx_k_20[] = "rankdir = LR;";
+  static char __pyx_k_21[] = "node [shape=circle];";
+  static char __pyx_k_22[] = "%d -> %d [label=\"%s\"];";
+  static char __pyx_k_23[] = "\"";
+  static char __pyx_k_24[] = "\\\"";
+  static char __pyx_k_26[] = "%d [shape=doublecircle]";
+static char __pyx_k_27[] = "}";
+static char __pyx_k_30[] = "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi";
+static char __pyx_k_31[] = "\n";
+static char __pyx_k_33[] = "Cannot convert type %s to str";
+static char __pyx_k_35[] = "candidate set index out of range";
+static char __pyx_k_37[] = "cannot initialize weights with %s";
+static char __pyx_k_40[] = "Cannot translate input type %s";
+static char __pyx_k__i[] = "i";
 static char __pyx_k__k[] = "k";
 static char __pyx_k__TER[] = "TER";
 static char __pyx_k__dot[] = "dot";
@@ -1121,20 +1220,27 @@ static char __pyx_k__inp[] = "inp";
 static char __pyx_k__plf[] = "plf";
 static char __pyx_k__BLEU[] = "BLEU";
 static char __pyx_k__eval[] = "eval";
+static char __pyx_k__join[] = "join";
 static char __pyx_k__name[] = "name";
 static char __pyx_k__open[] = "open";
 static char __pyx_k__refs[] = "refs";
 static char __pyx_k__self[] = "self";
 static char __pyx_k__utf8[] = "utf8";
 static char __pyx_k___cdec[] = "_cdec";
+static char __pyx_k__delta[] = "delta";
+static char __pyx_k__items[] = "items";
+static char __pyx_k__label[] = "label";
+static char __pyx_k__lines[] = "lines";
 static char __pyx_k__range[] = "range";
 static char __pyx_k__split[] = "split";
 static char __pyx_k__strip[] = "strip";
 static char __pyx_k__config[] = "config";
 static char __pyx_k__decode[] = "decode";
 static char __pyx_k__encode[] = "encode";
+static char __pyx_k__weight[] = "weight";
 static char __pyx_k__density[] = "density";
 static char __pyx_k__grammar[] = "grammar";
+static char __pyx_k__replace[] = "replace";
 static char __pyx_k__IBM_BLEU[] = "IBM_BLEU";
 static char __pyx_k__KeyError[] = "KeyError";
 static char __pyx_k____exit__[] = "__exit__";
@@ -1159,8 +1265,19 @@ static PyObject *__pyx_kp_s_13;
 static PyObject *__pyx_kp_s_14;
 static PyObject *__pyx_kp_s_19;
 static PyObject *__pyx_kp_s_2;
+static PyObject *__pyx_kp_s_20;
 static PyObject *__pyx_kp_s_21;
-static PyObject *__pyx_kp_s_25;
+static PyObject *__pyx_kp_s_22;
+static PyObject *__pyx_kp_s_23;
+static PyObject *__pyx_kp_s_24;
+static PyObject *__pyx_kp_s_26;
+static PyObject *__pyx_kp_s_27;
+static PyObject *__pyx_kp_s_30;
+static PyObject *__pyx_kp_s_31;
+static PyObject *__pyx_kp_s_33;
+static PyObject *__pyx_kp_s_35;
+static PyObject *__pyx_kp_s_37;
+static PyObject *__pyx_kp_s_40;
 static PyObject *__pyx_n_s__BLEU;
 static PyObject *__pyx_n_s__Exception;
 static PyObject *__pyx_n_s__IBM_BLEU;
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 static PyObject *__pyx_n_s__beam_alpha;
 static PyObject *__pyx_n_s__config;
 static PyObject *__pyx_n_s__decode;
+static PyObject *__pyx_n_s__delta;
 static PyObject *__pyx_n_s__density;
 static PyObject *__pyx_n_s__dot;
 static PyObject *__pyx_n_s__encode;
@@ -1187,18 +1305,25 @@ static PyObject *__pyx_n_s__eval;
 static PyObject *__pyx_n_s__evaluator;
 static PyObject *__pyx_n_s__grammar;
 static PyObject *__pyx_n_s__hypergraph;
+static PyObject *__pyx_n_s__i;
 static PyObject *__pyx_n_s__inp;
+static PyObject *__pyx_n_s__items;
+static PyObject *__pyx_n_s__join;
 static PyObject *__pyx_n_s__k;
+static PyObject *__pyx_n_s__label;
+static PyObject *__pyx_n_s__lines;
 static PyObject *__pyx_n_s__name;
 static PyObject *__pyx_n_s__open;
 static PyObject *__pyx_n_s__plf;
 static PyObject *__pyx_n_s__range;
 static PyObject *__pyx_n_s__refs;
+static PyObject *__pyx_n_s__replace;
 static PyObject *__pyx_n_s__self;
 static PyObject *__pyx_n_s__sentence;
 static PyObject *__pyx_n_s__split;
 static PyObject *__pyx_n_s__strip;
 static PyObject *__pyx_n_s__utf8;
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 static PyObject *__pyx_int_0;
 static PyObject *__pyx_int_1;
 static PyObject *__pyx_k_tuple_3;
@@ -1213,12 +1338,16 @@ static PyObject *__pyx_k_tuple_15;
 static PyObject *__pyx_k_tuple_16;
 static PyObject *__pyx_k_tuple_17;
 static PyObject *__pyx_k_tuple_18;
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-static PyObject *__pyx_k_tuple_26;
-static PyObject *__pyx_k_tuple_27;
+static PyObject *__pyx_k_tuple_25;
+static PyObject *__pyx_k_tuple_28;
+static PyObject *__pyx_k_tuple_32;
+static PyObject *__pyx_k_tuple_34;
+static PyObject *__pyx_k_tuple_36;
+static PyObject *__pyx_k_tuple_38;
+static PyObject *__pyx_k_tuple_39;
+static PyObject *__pyx_k_tuple_41;
+static PyObject *__pyx_k_tuple_42;
+static PyObject *__pyx_k_codeobj_29;
 
 /* Python wrapper */
 static Py_ssize_t __pyx_pw_5_cdec_11DenseVector_1__len__(PyObject *__pyx_v_self); /*proto*/
@@ -2602,7 +2731,7 @@ static int __pyx_pf_5_cdec_12SparseVector_17__contains__(struct __pyx_obj_5_cdec
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  *         return self.vector.nonzero(FDConvert(fname))             # <<<<<<<<<<<<<<
  * 
- *     def __iadd__(SparseVector self, SparseVector other):
+ *     def __neg__(self):
  */
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   goto __pyx_L0;
@@ -2614,13 +2743,97 @@ static int __pyx_pf_5_cdec_12SparseVector_17__contains__(struct __pyx_obj_5_cdec
 }
 
 /* Python wrapper */
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-static PyObject *__pyx_pw_5_cdec_12SparseVector_20__iadd__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
+static PyObject *__pyx_pw_5_cdec_12SparseVector_20__neg__(PyObject *__pyx_v_self); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_20__neg__(PyObject *__pyx_v_self) {
+  PyObject *__pyx_r = 0;
+  __Pyx_RefNannyDeclarations
+  __Pyx_RefNannySetupContext("__neg__ (wrapper)", 0);
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+  __Pyx_RefNannyFinishContext();
+  return __pyx_r;
+}
+
+/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":84
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+ * 
+ *     def __neg__(self):             # <<<<<<<<<<<<<<
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+ */
+
+static PyObject *__pyx_pf_5_cdec_12SparseVector_19__neg__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self) {
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+  PyObject *__pyx_r = NULL;
+  __Pyx_RefNannyDeclarations
+  PyObject *__pyx_t_1 = NULL;
+  int __pyx_lineno = 0;
+  const char *__pyx_filename = NULL;
+  int __pyx_clineno = 0;
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":85
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+ *         result.vector[0] *= -1.0
+ */
+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_SparseVector)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 85; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  __pyx_v_result = ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_t_1);
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":86
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+ *         return result
+ */
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+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":87
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+ * 
+ */
+  (__pyx_v_result->vector[0]) *= -1.0;
+
+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":88
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+ *         result.vector[0] *= -1.0
+ *         return result             # <<<<<<<<<<<<<<
+ * 
+ *     def __iadd__(SparseVector self, SparseVector other):
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+  __Pyx_INCREF(((PyObject *)__pyx_v_result));
+  __pyx_r = ((PyObject *)__pyx_v_result);
+  goto __pyx_L0;
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+  __pyx_r = Py_None; __Pyx_INCREF(Py_None);
+  goto __pyx_L0;
+  __pyx_L1_error:;
+  __Pyx_XDECREF(__pyx_t_1);
+  __Pyx_AddTraceback("_cdec.SparseVector.__neg__", __pyx_clineno, __pyx_lineno, __pyx_filename);
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+  __Pyx_XDECREF((PyObject *)__pyx_v_result);
+  __Pyx_XGIVEREF(__pyx_r);
+  __Pyx_RefNannyFinishContext();
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+/* Python wrapper */
+static PyObject *__pyx_pw_5_cdec_12SparseVector_22__iadd__(PyObject *__pyx_v_self, PyObject *__pyx_v_other); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_22__iadd__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
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-  __pyx_r = __pyx_pf_5_cdec_12SparseVector_19__iadd__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_other));
+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_other), __pyx_ptype_5_cdec_SparseVector, 1, "other", 0))) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 90; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_21__iadd__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_other));
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":84
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+/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":90
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-static PyObject *__pyx_pf_5_cdec_12SparseVector_19__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
+static PyObject *__pyx_pf_5_cdec_12SparseVector_21__iadd__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":85
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":86
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+static PyObject *__pyx_pw_5_cdec_12SparseVector_24__isub__(PyObject *__pyx_v_self, PyObject *__pyx_v_other); /*proto*/
+static PyObject *__pyx_pw_5_cdec_12SparseVector_24__isub__(PyObject *__pyx_v_self, PyObject *__pyx_v_other) {
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-  __pyx_r = __pyx_pf_5_cdec_12SparseVector_21__isub__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_other));
+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_other), __pyx_ptype_5_cdec_SparseVector, 1, "other", 0))) {__pyx_filename = __pyx_f[1]; __pyx_lineno = 94; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":88
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_23__isub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_other) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":89
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":90
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":94
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+  __pyx_r = __pyx_pf_5_cdec_12SparseVector_27__idiv__(((struct __pyx_obj_5_cdec_SparseVector *)__pyx_v_self), ((float)__pyx_v_scalar));
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":96
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_27__idiv__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_self, float __pyx_v_scalar) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":97
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":98
+  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":104
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_29__add__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":101
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":102
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":103
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-/* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":105
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+static PyObject *__pyx_pf_5_cdec_12SparseVector_31__sub__(struct __pyx_obj_5_cdec_SparseVector *__pyx_v_x, struct __pyx_obj_5_cdec_SparseVector *__pyx_v_y) {
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":106
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":107
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":108
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/vectors.pxi":116
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  *         cdef SufficientStats result = SufficientStats()             # <<<<<<<<<<<<<<
- *         result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))
- *         result.metric = x.metric
+ *         result.stats = new mteval.SufficientStats(mteval.add(sx.stats[0], sy.stats[0]))
+ *         result.metric = sx.metric
  */
-  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_SufficientStats)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 54; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_SufficientStats)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 65; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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   __pyx_t_1 = 0;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":55
- *     def __add__(SufficientStats x, SufficientStats y):
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":66
+ *         cdef SufficientStats sy = as_stats(y, x)
  *         cdef SufficientStats result = SufficientStats()
- *         result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))             # <<<<<<<<<<<<<<
- *         result.metric = x.metric
+ *         result.stats = new mteval.SufficientStats(mteval.add(sx.stats[0], sy.stats[0]))             # <<<<<<<<<<<<<<
+ *         result.metric = sx.metric
  *         return result
  */
-  __pyx_v_result->stats = new SufficientStats(operator+((__pyx_v_x->stats[0]), (__pyx_v_y->stats[0])));
+  __pyx_v_result->stats = new SufficientStats(operator+((__pyx_v_sx->stats[0]), (__pyx_v_sy->stats[0])));
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":56
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":67
  *         cdef SufficientStats result = SufficientStats()
- *         result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))
- *         result.metric = x.metric             # <<<<<<<<<<<<<<
+ *         result.stats = new mteval.SufficientStats(mteval.add(sx.stats[0], sy.stats[0]))
+ *         result.metric = sx.metric             # <<<<<<<<<<<<<<
  *         return result
  * 
  */
-  __pyx_v_result->metric = __pyx_v_x->metric;
+  __pyx_v_result->metric = __pyx_v_sx->metric;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":57
- *         result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))
- *         result.metric = x.metric
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":68
+ *         result.stats = new mteval.SufficientStats(mteval.add(sx.stats[0], sy.stats[0]))
+ *         result.metric = sx.metric
  *         return result             # <<<<<<<<<<<<<<
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   __pyx_r = NULL;
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+  __Pyx_XDECREF((PyObject *)__pyx_v_sx);
+  __Pyx_XDECREF((PyObject *)__pyx_v_sy);
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+        if (unlikely(__Pyx_ParseOptionalKeywords(__pyx_kwds, __pyx_pyargnames, 0, values, pos_args, "__cinit__") < 0)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 75; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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-  __Pyx_RaiseArgtupleInvalid("__cinit__", 1, 1, 1, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 64; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
+  __Pyx_RaiseArgtupleInvalid("__cinit__", 1, 1, 1, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 75; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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-  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_evaluator), __pyx_ptype_5_cdec_SegmentEvaluator, 1, "evaluator", 0))) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 64; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_evaluator), __pyx_ptype_5_cdec_SegmentEvaluator, 1, "evaluator", 0))) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 75; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -6845,7 +7725,7 @@ static int __pyx_pw_5_cdec_12CandidateSet_1__cinit__(PyObject *__pyx_v_self, PyO
   return __pyx_r;
 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":64
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":75
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":65
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":66
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":77
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   __pyx_v_self->metric = __pyx_v_evaluator->metric;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":67
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":78
  *         self.scorer = new shared_ptr[mteval.SegmentEvaluator](evaluator.scorer[0])
  *         self.metric = evaluator.metric
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-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":69
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":80
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  *     def __dealloc__(self):             # <<<<<<<<<<<<<<
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":70
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":81
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  *     def __dealloc__(self):
  *         del self.scorer             # <<<<<<<<<<<<<<
@@ -6920,7 +7800,7 @@ static void __pyx_pf_5_cdec_12CandidateSet_2__dealloc__(CYTHON_UNUSED struct __p
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   delete __pyx_v_self->scorer;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":71
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":82
  *     def __dealloc__(self):
  *         del self.scorer
  *         del self.cs             # <<<<<<<<<<<<<<
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-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":73
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":84
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":74
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  *     def __len__(self):
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-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":76
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":77
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":78
+    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":89
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+    __pyx_t_3 = PyObject_Call(__pyx_builtin_IndexError, ((PyObject *)__pyx_k_tuple_36), NULL); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 89; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-    {__pyx_filename = __pyx_f[4]; __pyx_lineno = 78; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+    {__pyx_filename = __pyx_f[4]; __pyx_lineno = 89; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":79
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":90
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-  __pyx_t_3 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Candidate)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 79; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_3 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Candidate)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 90; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":80
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":91
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":81
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":82
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-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":84
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-  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *__pyx_cur_scope;
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+  __pyx_cur_scope = (struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *)__pyx_ptype_5_cdec___pyx_scope_struct_10___iter__->tp_new(__pyx_ptype_5_cdec___pyx_scope_struct_10___iter__, __pyx_empty_tuple, NULL);
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":86
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-  __pyx_t_1 = PyObject_Length(((PyObject *)__pyx_cur_scope->__pyx_v_self)); if (unlikely(__pyx_t_1 == -1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 86; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_1 = PyObject_Length(((PyObject *)__pyx_cur_scope->__pyx_v_self)); if (unlikely(__pyx_t_1 == -1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 97; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   for (__pyx_t_2 = 0; __pyx_t_2 < __pyx_t_1; __pyx_t_2+=1) {
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":87
+    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":98
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-    __pyx_t_3 = __Pyx_GetItemInt(((PyObject *)__pyx_cur_scope->__pyx_v_self), __pyx_cur_scope->__pyx_v_i, sizeof(unsigned int)+1, PyLong_FromUnsignedLong); if (!__pyx_t_3) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 87; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+    __pyx_t_3 = __Pyx_GetItemInt(((PyObject *)__pyx_cur_scope->__pyx_v_self), __pyx_cur_scope->__pyx_v_i, sizeof(unsigned int)+1, PyLong_FromUnsignedLong); if (!__pyx_t_3) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 98; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -7205,7 +8085,7 @@ static PyObject *__pyx_gb_5_cdec_12CandidateSet_10generator8(__pyx_GeneratorObje
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-    if (unlikely(!__pyx_sent_value)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 87; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+    if (unlikely(!__pyx_sent_value)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 98; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -7249,11 +8129,11 @@ static PyObject *__pyx_pw_5_cdec_12CandidateSet_12add_kbest(PyObject *__pyx_v_se
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-          __Pyx_RaiseArgtupleInvalid("add_kbest", 1, 2, 2, 1); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 89; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
+          __Pyx_RaiseArgtupleInvalid("add_kbest", 1, 2, 2, 1); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 100; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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+    __pyx_v_k = __Pyx_PyInt_AsUnsignedInt(values[1]); if (unlikely((__pyx_v_k == (unsigned int)-1) && PyErr_Occurred())) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 100; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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-  __Pyx_RaiseArgtupleInvalid("add_kbest", 1, 2, 2, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 89; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
+  __Pyx_RaiseArgtupleInvalid("add_kbest", 1, 2, 2, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 100; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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+  if (unlikely(!__Pyx_ArgTypeTest(((PyObject *)__pyx_v_hypergraph), __pyx_ptype_5_cdec_Hypergraph, 1, "hypergraph", 0))) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 100; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -7282,7 +8162,7 @@ static PyObject *__pyx_pw_5_cdec_12CandidateSet_12add_kbest(PyObject *__pyx_v_se
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":89
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":100
  *             yield self[i]
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  *     def add_kbest(self, Hypergraph hypergraph, unsigned k):             # <<<<<<<<<<<<<<
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":90
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":101
  * 
  *     def add_kbest(self, Hypergraph hypergraph, unsigned k):
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":96
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":107
  *     cdef mteval.EvaluationMetric* metric
  * 
  *     def __dealloc__(self):             # <<<<<<<<<<<<<<
@@ -7331,7 +8211,7 @@ static void __pyx_pf_5_cdec_16SegmentEvaluator___dealloc__(CYTHON_UNUSED struct
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":97
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":108
  * 
  *     def __dealloc__(self):
  *         del self.scorer             # <<<<<<<<<<<<<<
@@ -7354,7 +8234,7 @@ static PyObject *__pyx_pw_5_cdec_16SegmentEvaluator_3evaluate(PyObject *__pyx_v_
   return __pyx_r;
 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":99
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":110
  *         del self.scorer
  * 
  *     def evaluate(self, sentence):             # <<<<<<<<<<<<<<
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":101
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":112
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  *         cdef vector[WordID] hyp
  *         cdef SufficientStats sf = SufficientStats()             # <<<<<<<<<<<<<<
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-  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_SufficientStats)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 101; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_SufficientStats)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 112; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":102
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":113
  *         cdef vector[WordID] hyp
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@@ -7395,7 +8275,7 @@ static PyObject *__pyx_pf_5_cdec_16SegmentEvaluator_2evaluate(struct __pyx_obj_5
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   __pyx_v_sf->metric = __pyx_v_self->metric;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":103
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":114
  *         cdef SufficientStats sf = SufficientStats()
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  *         sf.stats = new mteval.SufficientStats()             # <<<<<<<<<<<<<<
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":104
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":115
  *         sf.metric = self.metric
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+  __pyx_t_1 = PyObject_GetAttr(__pyx_v_sentence, __pyx_n_s__strip); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 115; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  __pyx_t_2 = PyObject_Call(__pyx_t_1, ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 104; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_2 = PyObject_Call(__pyx_t_1, ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 115; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":105
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":116
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@@ -7428,7 +8308,7 @@ static PyObject *__pyx_pf_5_cdec_16SegmentEvaluator_2evaluate(struct __pyx_obj_5
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":106
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":117
  *         ConvertSentence(string(as_str(sentence.strip())), &hyp)
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":108
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":119
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":109
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":120
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+  __pyx_t_1 = PyTuple_New(1); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 120; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  __pyx_t_2 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_CandidateSet)), ((PyObject *)__pyx_t_1), NULL); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 109; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_2 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_CandidateSet)), ((PyObject *)__pyx_t_1), NULL); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 120; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+        if (unlikely(__Pyx_ParseOptionalKeywords(__pyx_kwds, __pyx_pyargnames, 0, values, pos_args, "__cinit__") < 0)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 125; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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+    __pyx_v_name = PyBytes_AsString(values[0]); if (unlikely((!__pyx_v_name) && PyErr_Occurred())) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 125; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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-  __Pyx_RaiseArgtupleInvalid("__cinit__", 1, 1, 1, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 114; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
+  __Pyx_RaiseArgtupleInvalid("__cinit__", 1, 1, 1, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 125; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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@@ -7564,7 +8444,7 @@ static int __pyx_pw_5_cdec_6Scorer_1__cinit__(PyObject *__pyx_v_self, PyObject *
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":114
+/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":125
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":115
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":126
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-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":117
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":118
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+        if (unlikely(__Pyx_ParseOptionalKeywords(__pyx_kwds, __pyx_pyargnames, 0, values, pos_args, "__call__") < 0)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 131; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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@@ -7661,7 +8541,7 @@ static PyObject *__pyx_pw_5_cdec_6Scorer_5__call__(PyObject *__pyx_v_self, PyObj
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+  __Pyx_RaiseArgtupleInvalid("__call__", 1, 1, 1, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[4]; __pyx_lineno = 131; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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 }
 
-/* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":120
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":121
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":122
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":123
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":124
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":135
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":127
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":138
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":128
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":129
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":130
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-    /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":131
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":133
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":135
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":136
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":137
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@@ -8314,22 +9487,22 @@ static PyObject *__pyx_pf_5_cdec_7Decoder_4read_weights(struct __pyx_obj_5_cdec_
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-            /* "_cdec.pyx":34
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+            __pyx_t_1 = PyFloat_FromDouble(__pyx_t_13); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 50; __pyx_clineno = __LINE__; goto __pyx_L7_error;}
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+            __pyx_t_2 = PyObject_Call(__pyx_t_10, ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_2)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 50; __pyx_clineno = __LINE__; goto __pyx_L7_error;}
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-        /* "_cdec.pyx":31
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@@ -8355,11 +9528,11 @@ static PyObject *__pyx_pf_5_cdec_7Decoder_4read_weights(struct __pyx_obj_5_cdec_
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-        __pyx_t_7 = PyObject_Call(__pyx_t_3, __pyx_k_tuple_23, NULL);
+        __pyx_t_7 = PyObject_Call(__pyx_t_3, __pyx_k_tuple_38, NULL);
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-        if (unlikely(!__pyx_t_7)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 31; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+        if (unlikely(!__pyx_t_7)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 47; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-    /* "_cdec.pyx":36
+    /* "_cdec.pyx":52
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+        if (unlikely(__Pyx_ParseOptionalKeywords(__pyx_kwds, __pyx_pyargnames, 0, values, pos_args, "translate") < 0)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 52; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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@@ -8503,7 +9676,7 @@ static PyObject *__pyx_pw_5_cdec_7Decoder_7translate(PyObject *__pyx_v_self, PyO
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+  __Pyx_RaiseArgtupleInvalid("translate", 0, 1, 2, PyTuple_GET_SIZE(__pyx_args)); {__pyx_filename = __pyx_f[0]; __pyx_lineno = 52; __pyx_clineno = __LINE__; goto __pyx_L3_error;}
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-    /* "_cdec.pyx":38
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-    __pyx_t_3 = PyObject_Call(__pyx_t_1, ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 38; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "_cdec.pyx":39
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-    /* "_cdec.pyx":42
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-    /* "_cdec.pyx":44
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+  __pyx_t_2 = __Pyx_PyObject_IsTrue(__pyx_v_grammar); if (unlikely(__pyx_t_2 < 0)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 61; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   if (__pyx_t_2) {
 
-    /* "_cdec.pyx":46
+    /* "_cdec.pyx":62
  *             raise TypeError('Cannot translate input type %s' % type(sentence))
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  *             self.dec.SetSentenceGrammarFromString(string(<char *> grammar))             # <<<<<<<<<<<<<<
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-    __pyx_t_4 = PyBytes_AsString(__pyx_v_grammar); if (unlikely((!__pyx_t_4) && PyErr_Occurred())) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 46; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+    __pyx_t_4 = PyBytes_AsString(__pyx_v_grammar); if (unlikely((!__pyx_t_4) && PyErr_Occurred())) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 62; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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     goto __pyx_L4;
   }
   __pyx_L4:;
 
-  /* "_cdec.pyx":47
+  /* "_cdec.pyx":63
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  *         cdef decoder.BasicObserver observer = decoder.BasicObserver()             # <<<<<<<<<<<<<<
@@ -8684,17 +9857,17 @@ static PyObject *__pyx_pf_5_cdec_7Decoder_6translate(struct __pyx_obj_5_cdec_Dec
  */
   __pyx_v_observer = BasicObserver();
 
-  /* "_cdec.pyx":48
+  /* "_cdec.pyx":64
  *             self.dec.SetSentenceGrammarFromString(string(<char *> grammar))
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  *         self.dec.Decode(string(<char *>inp), &observer)             # <<<<<<<<<<<<<<
  *         if observer.hypergraph == NULL:
  *             raise ParseFailed()
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-  __pyx_t_4 = PyBytes_AsString(__pyx_v_inp); if (unlikely((!__pyx_t_4) && PyErr_Occurred())) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 48; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_t_4 = PyBytes_AsString(__pyx_v_inp); if (unlikely((!__pyx_t_4) && PyErr_Occurred())) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 64; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __pyx_v_self->dec->Decode(std::string(((char *)__pyx_t_4)), (&__pyx_v_observer));
 
-  /* "_cdec.pyx":49
+  /* "_cdec.pyx":65
  *         cdef decoder.BasicObserver observer = decoder.BasicObserver()
  *         self.dec.Decode(string(<char *>inp), &observer)
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-    /* "_cdec.pyx":50
+    /* "_cdec.pyx":66
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+    __pyx_t_3 = __Pyx_GetName(__pyx_m, __pyx_n_s__ParseFailed); if (unlikely(!__pyx_t_3)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 66; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+    __pyx_t_1 = PyObject_Call(__pyx_t_3, ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 66; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-    {__pyx_filename = __pyx_f[0]; __pyx_lineno = 50; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+    {__pyx_filename = __pyx_f[0]; __pyx_lineno = 66; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "_cdec.pyx":51
+  /* "_cdec.pyx":67
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+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Hypergraph)), ((PyObject *)__pyx_empty_tuple), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 67; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  /* "_cdec.pyx":52
+  /* "_cdec.pyx":68
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-  /* "_cdec.pyx":53
+  /* "_cdec.pyx":69
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  *         return hg             # <<<<<<<<<<<<<<
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-static PyObject *__pyx_pw_5_cdec_7Decoder_7weights_1__get__(PyObject *__pyx_v_self); /*proto*/
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- * 
- *     def __cinit__(self, char* config):
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-
-static PyObject *__pyx_pf_5_cdec_7Decoder_7weights___get__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self) {
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-  __pyx_r = Py_None; __Pyx_INCREF(Py_None);
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-static int __pyx_pf_5_cdec_7Decoder_7weights_2__set__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self, PyObject *__pyx_v_value) {
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-  __Pyx_INCREF(__pyx_v_value);
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-  __Pyx_DECREF(((PyObject *)__pyx_v_self->weights));
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-
-  __pyx_r = 0;
-  goto __pyx_L0;
-  __pyx_L1_error:;
-  __Pyx_AddTraceback("_cdec.Decoder.weights.__set__", __pyx_clineno, __pyx_lineno, __pyx_filename);
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-static int __pyx_pw_5_cdec_7Decoder_7weights_5__del__(PyObject *__pyx_v_self) {
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-  __Pyx_RefNannyDeclarations
-  __Pyx_RefNannySetupContext("__del__ (wrapper)", 0);
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-  __Pyx_RefNannyFinishContext();
-  return __pyx_r;
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-
-static int __pyx_pf_5_cdec_7Decoder_7weights_4__del__(struct __pyx_obj_5_cdec_Decoder *__pyx_v_self) {
-  int __pyx_r;
-  __Pyx_RefNannyDeclarations
-  __Pyx_RefNannySetupContext("__del__", 0);
-  __Pyx_INCREF(Py_None);
-  __Pyx_GIVEREF(Py_None);
-  __Pyx_GOTREF(__pyx_v_self->weights);
-  __Pyx_DECREF(((PyObject *)__pyx_v_self->weights));
-  __pyx_v_self->weights = ((struct __pyx_obj_5_cdec_DenseVector *)Py_None);
-
-  __pyx_r = 0;
-  __Pyx_RefNannyFinishContext();
-  return __pyx_r;
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-
 static PyObject *__pyx_tp_new_5_cdec_DenseVector(PyTypeObject *t, PyObject *a, PyObject *k) {
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@@ -9096,16 +10173,16 @@ static PyMethodDef __pyx_methods_5_cdec_SparseVector[] = {
 };
 
 static PyNumberMethods __pyx_tp_as_number_SparseVector = {
-  __pyx_pw_5_cdec_12SparseVector_28__add__, /*nb_add*/
-  __pyx_pw_5_cdec_12SparseVector_30__sub__, /*nb_subtract*/
-  __pyx_pw_5_cdec_12SparseVector_32__mul__, /*nb_multiply*/
+  __pyx_pw_5_cdec_12SparseVector_30__add__, /*nb_add*/
+  __pyx_pw_5_cdec_12SparseVector_32__sub__, /*nb_subtract*/
+  __pyx_pw_5_cdec_12SparseVector_34__mul__, /*nb_multiply*/
   #if PY_MAJOR_VERSION < 3
-  __pyx_pw_5_cdec_12SparseVector_34__div__, /*nb_divide*/
+  __pyx_pw_5_cdec_12SparseVector_36__div__, /*nb_divide*/
   #endif
   0, /*nb_remainder*/
   0, /*nb_divmod*/
   0, /*nb_power*/
-  0, /*nb_negative*/
+  __pyx_pw_5_cdec_12SparseVector_20__neg__, /*nb_negative*/
   0, /*nb_positive*/
   0, /*nb_absolute*/
   0, /*nb_nonzero*/
@@ -9131,11 +10208,11 @@ static PyNumberMethods __pyx_tp_as_number_SparseVector = {
   #if PY_MAJOR_VERSION < 3
   0, /*nb_hex*/
   #endif
-  __pyx_pw_5_cdec_12SparseVector_20__iadd__, /*nb_inplace_add*/
-  __pyx_pw_5_cdec_12SparseVector_22__isub__, /*nb_inplace_subtract*/
-  __pyx_pw_5_cdec_12SparseVector_24__imul__, /*nb_inplace_multiply*/
+  __pyx_pw_5_cdec_12SparseVector_22__iadd__, /*nb_inplace_add*/
+  __pyx_pw_5_cdec_12SparseVector_24__isub__, /*nb_inplace_subtract*/
+  __pyx_pw_5_cdec_12SparseVector_26__imul__, /*nb_inplace_multiply*/
   #if PY_MAJOR_VERSION < 3
-  __pyx_pw_5_cdec_12SparseVector_26__idiv__, /*nb_inplace_divide*/
+  __pyx_pw_5_cdec_12SparseVector_28__idiv__, /*nb_inplace_divide*/
   #endif
   0, /*nb_inplace_remainder*/
   0, /*nb_inplace_power*/
@@ -9476,6 +10553,7 @@ static int __pyx_mp_ass_subscript_5_cdec_Lattice(PyObject *o, PyObject *i, PyObj
 }
 
 static PyMethodDef __pyx_methods_5_cdec_Lattice[] = {
+  {__Pyx_NAMESTR("todot"), (PyCFunction)__pyx_pw_5_cdec_7Lattice_16todot, METH_NOARGS, __Pyx_DOCSTR(0)},
   {0, 0, 0, 0}
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@@ -10622,7 +11700,8 @@ static int __pyx_setprop_5_cdec_7Decoder_weights(PyObject *o, PyObject *v, void
     return __pyx_pw_5_cdec_7Decoder_7weights_3__set__(o, v);
   }
   else {
-    return __pyx_pw_5_cdec_7Decoder_7weights_5__del__(o);
+    PyErr_SetString(PyExc_NotImplementedError, "__del__");
+    return -1;
   }
 }
 
@@ -12184,28 +13263,458 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_6___iter__ = {
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 };
 
-static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_7___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p;
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_7_todot(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *p;
   PyObject *o = (*t->tp_alloc)(t, 0);
   if (!o) return 0;
-  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o);
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *)o);
+  p->__pyx_v_self = 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7_todot(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *)o;
+  Py_XDECREF(((PyObject *)p->__pyx_v_self));
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_7_todot(PyObject *o, visitproc v, void *a) {
+  int e;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *)o;
+  if (p->__pyx_v_self) {
+    e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
+  }
+  return 0;
+}
+
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_7_todot(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *)o;
+  PyObject* tmp;
+  tmp = ((PyObject*)p->__pyx_v_self);
+  p->__pyx_v_self = ((struct __pyx_obj_5_cdec_Lattice *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  return 0;
+}
+
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_7_todot[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_7_todot = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
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+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
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+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
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+  0, /*nb_index*/
+  #endif
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+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_7_todot = {
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+  0, /*sq_concat*/
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+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_7_todot = {
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+  0, /*mp_subscript*/
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+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_7_todot = {
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+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
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+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
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+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
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+
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7_todot = {
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+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_7_todot"), /*tp_name*/
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+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7_todot, /*tp_dealloc*/
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+  &__pyx_tp_as_mapping___pyx_scope_struct_7_todot, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_7_todot, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+  0, /*tp_doc*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_7_todot, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_7_todot, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec___pyx_scope_struct_7_todot, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_7_todot, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_8_lines(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *p;
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *)o);
+  p->__pyx_outer_scope = 0;
+  p->__pyx_v_delta = 0;
+  p->__pyx_v_i = 0;
+  p->__pyx_v_label = 0;
+  p->__pyx_v_weight = 0;
+  p->__pyx_t_1 = 0;
+  p->__pyx_t_3 = 0;
+  return o;
+}
+
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8_lines(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *)o;
+  Py_XDECREF(((PyObject *)p->__pyx_outer_scope));
+  Py_XDECREF(p->__pyx_v_delta);
+  Py_XDECREF(p->__pyx_v_i);
+  Py_XDECREF(p->__pyx_v_label);
+  Py_XDECREF(p->__pyx_v_weight);
+  Py_XDECREF(p->__pyx_t_1);
+  Py_XDECREF(p->__pyx_t_3);
+  (*Py_TYPE(o)->tp_free)(o);
+}
+
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_8_lines(PyObject *o, visitproc v, void *a) {
+  int e;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *)o;
+  if (p->__pyx_outer_scope) {
+    e = (*v)(((PyObject*)p->__pyx_outer_scope), a); if (e) return e;
+  }
+  if (p->__pyx_v_delta) {
+    e = (*v)(p->__pyx_v_delta, a); if (e) return e;
+  }
+  if (p->__pyx_v_i) {
+    e = (*v)(p->__pyx_v_i, a); if (e) return e;
+  }
+  if (p->__pyx_v_label) {
+    e = (*v)(p->__pyx_v_label, a); if (e) return e;
+  }
+  if (p->__pyx_v_weight) {
+    e = (*v)(p->__pyx_v_weight, a); if (e) return e;
+  }
+  if (p->__pyx_t_1) {
+    e = (*v)(p->__pyx_t_1, a); if (e) return e;
+  }
+  if (p->__pyx_t_3) {
+    e = (*v)(p->__pyx_t_3, a); if (e) return e;
+  }
+  return 0;
+}
+
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_8_lines(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines *)o;
+  PyObject* tmp;
+  tmp = ((PyObject*)p->__pyx_outer_scope);
+  p->__pyx_outer_scope = ((struct __pyx_obj_5_cdec___pyx_scope_struct_7_todot *)Py_None); Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_delta);
+  p->__pyx_v_delta = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_i);
+  p->__pyx_v_i = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_label);
+  p->__pyx_v_label = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_v_weight);
+  p->__pyx_v_weight = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_t_1);
+  p->__pyx_t_1 = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  tmp = ((PyObject*)p->__pyx_t_3);
+  p->__pyx_t_3 = Py_None; Py_INCREF(Py_None);
+  Py_XDECREF(tmp);
+  return 0;
+}
+
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_8_lines[] = {
+  {0, 0, 0, 0}
+};
+
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_8_lines = {
+  0, /*nb_add*/
+  0, /*nb_subtract*/
+  0, /*nb_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_divide*/
+  #endif
+  0, /*nb_remainder*/
+  0, /*nb_divmod*/
+  0, /*nb_power*/
+  0, /*nb_negative*/
+  0, /*nb_positive*/
+  0, /*nb_absolute*/
+  0, /*nb_nonzero*/
+  0, /*nb_invert*/
+  0, /*nb_lshift*/
+  0, /*nb_rshift*/
+  0, /*nb_and*/
+  0, /*nb_xor*/
+  0, /*nb_or*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_coerce*/
+  #endif
+  0, /*nb_int*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_long*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*nb_float*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_oct*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_hex*/
+  #endif
+  0, /*nb_inplace_add*/
+  0, /*nb_inplace_subtract*/
+  0, /*nb_inplace_multiply*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*nb_inplace_divide*/
+  #endif
+  0, /*nb_inplace_remainder*/
+  0, /*nb_inplace_power*/
+  0, /*nb_inplace_lshift*/
+  0, /*nb_inplace_rshift*/
+  0, /*nb_inplace_and*/
+  0, /*nb_inplace_xor*/
+  0, /*nb_inplace_or*/
+  0, /*nb_floor_divide*/
+  0, /*nb_true_divide*/
+  0, /*nb_inplace_floor_divide*/
+  0, /*nb_inplace_true_divide*/
+  #if PY_VERSION_HEX >= 0x02050000
+  0, /*nb_index*/
+  #endif
+};
+
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_8_lines = {
+  0, /*sq_length*/
+  0, /*sq_concat*/
+  0, /*sq_repeat*/
+  0, /*sq_item*/
+  0, /*sq_slice*/
+  0, /*sq_ass_item*/
+  0, /*sq_ass_slice*/
+  0, /*sq_contains*/
+  0, /*sq_inplace_concat*/
+  0, /*sq_inplace_repeat*/
+};
+
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_8_lines = {
+  0, /*mp_length*/
+  0, /*mp_subscript*/
+  0, /*mp_ass_subscript*/
+};
+
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_8_lines = {
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getreadbuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getwritebuffer*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getsegcount*/
+  #endif
+  #if PY_MAJOR_VERSION < 3
+  0, /*bf_getcharbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_getbuffer*/
+  #endif
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*bf_releasebuffer*/
+  #endif
+};
+
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_8_lines = {
+  PyVarObject_HEAD_INIT(0, 0)
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_8_lines"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_8_lines), /*tp_basicsize*/
+  0, /*tp_itemsize*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8_lines, /*tp_dealloc*/
+  0, /*tp_print*/
+  0, /*tp_getattr*/
+  0, /*tp_setattr*/
+  #if PY_MAJOR_VERSION < 3
+  0, /*tp_compare*/
+  #else
+  0, /*reserved*/
+  #endif
+  0, /*tp_repr*/
+  &__pyx_tp_as_number___pyx_scope_struct_8_lines, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_8_lines, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_8_lines, /*tp_as_mapping*/
+  0, /*tp_hash*/
+  0, /*tp_call*/
+  0, /*tp_str*/
+  0, /*tp_getattro*/
+  0, /*tp_setattro*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_8_lines, /*tp_as_buffer*/
+  Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+  0, /*tp_doc*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_8_lines, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_8_lines, /*tp_clear*/
+  0, /*tp_richcompare*/
+  0, /*tp_weaklistoffset*/
+  0, /*tp_iter*/
+  0, /*tp_iternext*/
+  __pyx_methods_5_cdec___pyx_scope_struct_8_lines, /*tp_methods*/
+  0, /*tp_members*/
+  0, /*tp_getset*/
+  0, /*tp_base*/
+  0, /*tp_dict*/
+  0, /*tp_descr_get*/
+  0, /*tp_descr_set*/
+  0, /*tp_dictoffset*/
+  0, /*tp_init*/
+  0, /*tp_alloc*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_8_lines, /*tp_new*/
+  0, /*tp_free*/
+  0, /*tp_is_gc*/
+  0, /*tp_bases*/
+  0, /*tp_mro*/
+  0, /*tp_cache*/
+  0, /*tp_subclasses*/
+  0, /*tp_weaklist*/
+  0, /*tp_del*/
+  #if PY_VERSION_HEX >= 0x02060000
+  0, /*tp_version_tag*/
+  #endif
+};
+
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_9___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *p;
+  PyObject *o = (*t->tp_alloc)(t, 0);
+  if (!o) return 0;
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *)o);
   p->__pyx_v_i = 0;
   p->__pyx_v_self = 0;
   p->__pyx_t_1 = 0;
   return o;
 }
 
-static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_9___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *)o;
   Py_XDECREF(p->__pyx_v_i);
   Py_XDECREF(((PyObject *)p->__pyx_v_self));
   Py_XDECREF(p->__pyx_t_1);
   (*Py_TYPE(o)->tp_free)(o);
 }
 
-static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_7___iter__(PyObject *o, visitproc v, void *a) {
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_9___iter__(PyObject *o, visitproc v, void *a) {
   int e;
-  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *)o;
   if (p->__pyx_v_i) {
     e = (*v)(p->__pyx_v_i, a); if (e) return e;
   }
@@ -12218,8 +13727,8 @@ static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_7___iter__(PyObject *o, v
   return 0;
 }
 
-static int __pyx_tp_clear_5_cdec___pyx_scope_struct_7___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__ *)o;
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_9___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__ *)o;
   PyObject* tmp;
   tmp = ((PyObject*)p->__pyx_v_i);
   p->__pyx_v_i = Py_None; Py_INCREF(Py_None);
@@ -12233,11 +13742,11 @@ static int __pyx_tp_clear_5_cdec___pyx_scope_struct_7___iter__(PyObject *o) {
   return 0;
 }
 
-static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_7___iter__[] = {
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_9___iter__[] = {
   {0, 0, 0, 0}
 };
 
-static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_7___iter__ = {
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_9___iter__ = {
   0, /*nb_add*/
   0, /*nb_subtract*/
   0, /*nb_multiply*/
@@ -12295,7 +13804,7 @@ static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_7___iter__ = {
   #endif
 };
 
-static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_7___iter__ = {
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_9___iter__ = {
   0, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
@@ -12308,13 +13817,13 @@ static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_7___iter__ = {
   0, /*sq_inplace_repeat*/
 };
 
-static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_7___iter__ = {
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_9___iter__ = {
   0, /*mp_length*/
   0, /*mp_subscript*/
   0, /*mp_ass_subscript*/
 };
 
-static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_7___iter__ = {
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_9___iter__ = {
   #if PY_MAJOR_VERSION < 3
   0, /*bf_getreadbuffer*/
   #endif
@@ -12335,12 +13844,12 @@ static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_7___iter__ = {
   #endif
 };
 
-static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7___iter__ = {
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_9___iter__ = {
   PyVarObject_HEAD_INIT(0, 0)
-  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_7___iter__"), /*tp_name*/
-  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_7___iter__), /*tp_basicsize*/
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_9___iter__"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_9___iter__), /*tp_basicsize*/
   0, /*tp_itemsize*/
-  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_7___iter__, /*tp_dealloc*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_9___iter__, /*tp_dealloc*/
   0, /*tp_print*/
   0, /*tp_getattr*/
   0, /*tp_setattr*/
@@ -12350,24 +13859,24 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7___iter__ = {
   0, /*reserved*/
   #endif
   0, /*tp_repr*/
-  &__pyx_tp_as_number___pyx_scope_struct_7___iter__, /*tp_as_number*/
-  &__pyx_tp_as_sequence___pyx_scope_struct_7___iter__, /*tp_as_sequence*/
-  &__pyx_tp_as_mapping___pyx_scope_struct_7___iter__, /*tp_as_mapping*/
+  &__pyx_tp_as_number___pyx_scope_struct_9___iter__, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_9___iter__, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_9___iter__, /*tp_as_mapping*/
   0, /*tp_hash*/
   0, /*tp_call*/
   0, /*tp_str*/
   0, /*tp_getattro*/
   0, /*tp_setattro*/
-  &__pyx_tp_as_buffer___pyx_scope_struct_7___iter__, /*tp_as_buffer*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_9___iter__, /*tp_as_buffer*/
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
   0, /*tp_doc*/
-  __pyx_tp_traverse_5_cdec___pyx_scope_struct_7___iter__, /*tp_traverse*/
-  __pyx_tp_clear_5_cdec___pyx_scope_struct_7___iter__, /*tp_clear*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_9___iter__, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_9___iter__, /*tp_clear*/
   0, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
   0, /*tp_iter*/
   0, /*tp_iternext*/
-  __pyx_methods_5_cdec___pyx_scope_struct_7___iter__, /*tp_methods*/
+  __pyx_methods_5_cdec___pyx_scope_struct_9___iter__, /*tp_methods*/
   0, /*tp_members*/
   0, /*tp_getset*/
   0, /*tp_base*/
@@ -12377,7 +13886,7 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7___iter__ = {
   0, /*tp_dictoffset*/
   0, /*tp_init*/
   0, /*tp_alloc*/
-  __pyx_tp_new_5_cdec___pyx_scope_struct_7___iter__, /*tp_new*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_9___iter__, /*tp_new*/
   0, /*tp_free*/
   0, /*tp_is_gc*/
   0, /*tp_bases*/
@@ -12391,32 +13900,32 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_7___iter__ = {
   #endif
 };
 
-static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_8___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p;
+static PyObject *__pyx_tp_new_5_cdec___pyx_scope_struct_10___iter__(PyTypeObject *t, PyObject *a, PyObject *k) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *p;
   PyObject *o = (*t->tp_alloc)(t, 0);
   if (!o) return 0;
-  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o);
+  p = ((struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *)o);
   p->__pyx_v_self = 0;
   return o;
 }
 
-static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+static void __pyx_tp_dealloc_5_cdec___pyx_scope_struct_10___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *)o;
   Py_XDECREF(((PyObject *)p->__pyx_v_self));
   (*Py_TYPE(o)->tp_free)(o);
 }
 
-static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_8___iter__(PyObject *o, visitproc v, void *a) {
+static int __pyx_tp_traverse_5_cdec___pyx_scope_struct_10___iter__(PyObject *o, visitproc v, void *a) {
   int e;
-  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+  struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *)o;
   if (p->__pyx_v_self) {
     e = (*v)(((PyObject*)p->__pyx_v_self), a); if (e) return e;
   }
   return 0;
 }
 
-static int __pyx_tp_clear_5_cdec___pyx_scope_struct_8___iter__(PyObject *o) {
-  struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__ *)o;
+static int __pyx_tp_clear_5_cdec___pyx_scope_struct_10___iter__(PyObject *o) {
+  struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *p = (struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__ *)o;
   PyObject* tmp;
   tmp = ((PyObject*)p->__pyx_v_self);
   p->__pyx_v_self = ((struct __pyx_obj_5_cdec_CandidateSet *)Py_None); Py_INCREF(Py_None);
@@ -12424,11 +13933,11 @@ static int __pyx_tp_clear_5_cdec___pyx_scope_struct_8___iter__(PyObject *o) {
   return 0;
 }
 
-static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_8___iter__[] = {
+static PyMethodDef __pyx_methods_5_cdec___pyx_scope_struct_10___iter__[] = {
   {0, 0, 0, 0}
 };
 
-static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_8___iter__ = {
+static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_10___iter__ = {
   0, /*nb_add*/
   0, /*nb_subtract*/
   0, /*nb_multiply*/
@@ -12486,7 +13995,7 @@ static PyNumberMethods __pyx_tp_as_number___pyx_scope_struct_8___iter__ = {
   #endif
 };
 
-static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_8___iter__ = {
+static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_10___iter__ = {
   0, /*sq_length*/
   0, /*sq_concat*/
   0, /*sq_repeat*/
@@ -12499,13 +14008,13 @@ static PySequenceMethods __pyx_tp_as_sequence___pyx_scope_struct_8___iter__ = {
   0, /*sq_inplace_repeat*/
 };
 
-static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_8___iter__ = {
+static PyMappingMethods __pyx_tp_as_mapping___pyx_scope_struct_10___iter__ = {
   0, /*mp_length*/
   0, /*mp_subscript*/
   0, /*mp_ass_subscript*/
 };
 
-static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_8___iter__ = {
+static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_10___iter__ = {
   #if PY_MAJOR_VERSION < 3
   0, /*bf_getreadbuffer*/
   #endif
@@ -12526,12 +14035,12 @@ static PyBufferProcs __pyx_tp_as_buffer___pyx_scope_struct_8___iter__ = {
   #endif
 };
 
-static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_8___iter__ = {
+static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_10___iter__ = {
   PyVarObject_HEAD_INIT(0, 0)
-  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_8___iter__"), /*tp_name*/
-  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_8___iter__), /*tp_basicsize*/
+  __Pyx_NAMESTR("_cdec.__pyx_scope_struct_10___iter__"), /*tp_name*/
+  sizeof(struct __pyx_obj_5_cdec___pyx_scope_struct_10___iter__), /*tp_basicsize*/
   0, /*tp_itemsize*/
-  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_8___iter__, /*tp_dealloc*/
+  __pyx_tp_dealloc_5_cdec___pyx_scope_struct_10___iter__, /*tp_dealloc*/
   0, /*tp_print*/
   0, /*tp_getattr*/
   0, /*tp_setattr*/
@@ -12541,24 +14050,24 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_8___iter__ = {
   0, /*reserved*/
   #endif
   0, /*tp_repr*/
-  &__pyx_tp_as_number___pyx_scope_struct_8___iter__, /*tp_as_number*/
-  &__pyx_tp_as_sequence___pyx_scope_struct_8___iter__, /*tp_as_sequence*/
-  &__pyx_tp_as_mapping___pyx_scope_struct_8___iter__, /*tp_as_mapping*/
+  &__pyx_tp_as_number___pyx_scope_struct_10___iter__, /*tp_as_number*/
+  &__pyx_tp_as_sequence___pyx_scope_struct_10___iter__, /*tp_as_sequence*/
+  &__pyx_tp_as_mapping___pyx_scope_struct_10___iter__, /*tp_as_mapping*/
   0, /*tp_hash*/
   0, /*tp_call*/
   0, /*tp_str*/
   0, /*tp_getattro*/
   0, /*tp_setattro*/
-  &__pyx_tp_as_buffer___pyx_scope_struct_8___iter__, /*tp_as_buffer*/
+  &__pyx_tp_as_buffer___pyx_scope_struct_10___iter__, /*tp_as_buffer*/
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
   0, /*tp_doc*/
-  __pyx_tp_traverse_5_cdec___pyx_scope_struct_8___iter__, /*tp_traverse*/
-  __pyx_tp_clear_5_cdec___pyx_scope_struct_8___iter__, /*tp_clear*/
+  __pyx_tp_traverse_5_cdec___pyx_scope_struct_10___iter__, /*tp_traverse*/
+  __pyx_tp_clear_5_cdec___pyx_scope_struct_10___iter__, /*tp_clear*/
   0, /*tp_richcompare*/
   0, /*tp_weaklistoffset*/
   0, /*tp_iter*/
   0, /*tp_iternext*/
-  __pyx_methods_5_cdec___pyx_scope_struct_8___iter__, /*tp_methods*/
+  __pyx_methods_5_cdec___pyx_scope_struct_10___iter__, /*tp_methods*/
   0, /*tp_members*/
   0, /*tp_getset*/
   0, /*tp_base*/
@@ -12568,7 +14077,7 @@ static PyTypeObject __pyx_type_5_cdec___pyx_scope_struct_8___iter__ = {
   0, /*tp_dictoffset*/
   0, /*tp_init*/
   0, /*tp_alloc*/
-  __pyx_tp_new_5_cdec___pyx_scope_struct_8___iter__, /*tp_new*/
+  __pyx_tp_new_5_cdec___pyx_scope_struct_10___iter__, /*tp_new*/
   0, /*tp_free*/
   0, /*tp_is_gc*/
   0, /*tp_bases*/
@@ -12608,8 +14117,19 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
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   {&__pyx_kp_s_2, __pyx_k_2, sizeof(__pyx_k_2), 0, 0, 1, 0},
+  {&__pyx_kp_s_20, __pyx_k_20, sizeof(__pyx_k_20), 0, 0, 1, 0},
   {&__pyx_kp_s_21, __pyx_k_21, sizeof(__pyx_k_21), 0, 0, 1, 0},
-  {&__pyx_kp_s_25, __pyx_k_25, sizeof(__pyx_k_25), 0, 0, 1, 0},
+  {&__pyx_kp_s_22, __pyx_k_22, sizeof(__pyx_k_22), 0, 0, 1, 0},
+  {&__pyx_kp_s_23, __pyx_k_23, sizeof(__pyx_k_23), 0, 0, 1, 0},
+  {&__pyx_kp_s_24, __pyx_k_24, sizeof(__pyx_k_24), 0, 0, 1, 0},
+  {&__pyx_kp_s_26, __pyx_k_26, sizeof(__pyx_k_26), 0, 0, 1, 0},
+  {&__pyx_kp_s_27, __pyx_k_27, sizeof(__pyx_k_27), 0, 0, 1, 0},
+  {&__pyx_kp_s_30, __pyx_k_30, sizeof(__pyx_k_30), 0, 0, 1, 0},
+  {&__pyx_kp_s_31, __pyx_k_31, sizeof(__pyx_k_31), 0, 0, 1, 0},
+  {&__pyx_kp_s_33, __pyx_k_33, sizeof(__pyx_k_33), 0, 0, 1, 0},
+  {&__pyx_kp_s_35, __pyx_k_35, sizeof(__pyx_k_35), 0, 0, 1, 0},
+  {&__pyx_kp_s_37, __pyx_k_37, sizeof(__pyx_k_37), 0, 0, 1, 0},
+  {&__pyx_kp_s_40, __pyx_k_40, sizeof(__pyx_k_40), 0, 0, 1, 0},
   {&__pyx_n_s__BLEU, __pyx_k__BLEU, sizeof(__pyx_k__BLEU), 0, 0, 1, 1},
   {&__pyx_n_s__Exception, __pyx_k__Exception, sizeof(__pyx_k__Exception), 0, 0, 1, 1},
   {&__pyx_n_s__IBM_BLEU, __pyx_k__IBM_BLEU, sizeof(__pyx_k__IBM_BLEU), 0, 0, 1, 1},
@@ -12627,6 +14147,7 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
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   {&__pyx_n_s__config, __pyx_k__config, sizeof(__pyx_k__config), 0, 0, 1, 1},
   {&__pyx_n_s__decode, __pyx_k__decode, sizeof(__pyx_k__decode), 0, 0, 1, 1},
+  {&__pyx_n_s__delta, __pyx_k__delta, sizeof(__pyx_k__delta), 0, 0, 1, 1},
   {&__pyx_n_s__density, __pyx_k__density, sizeof(__pyx_k__density), 0, 0, 1, 1},
   {&__pyx_n_s__dot, __pyx_k__dot, sizeof(__pyx_k__dot), 0, 0, 1, 1},
   {&__pyx_n_s__encode, __pyx_k__encode, sizeof(__pyx_k__encode), 0, 0, 1, 1},
@@ -12636,18 +14157,25 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
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   {&__pyx_n_s__hypergraph, __pyx_k__hypergraph, sizeof(__pyx_k__hypergraph), 0, 0, 1, 1},
+  {&__pyx_n_s__i, __pyx_k__i, sizeof(__pyx_k__i), 0, 0, 1, 1},
   {&__pyx_n_s__inp, __pyx_k__inp, sizeof(__pyx_k__inp), 0, 0, 1, 1},
+  {&__pyx_n_s__items, __pyx_k__items, sizeof(__pyx_k__items), 0, 0, 1, 1},
+  {&__pyx_n_s__join, __pyx_k__join, sizeof(__pyx_k__join), 0, 0, 1, 1},
   {&__pyx_n_s__k, __pyx_k__k, sizeof(__pyx_k__k), 0, 0, 1, 1},
+  {&__pyx_n_s__label, __pyx_k__label, sizeof(__pyx_k__label), 0, 0, 1, 1},
+  {&__pyx_n_s__lines, __pyx_k__lines, sizeof(__pyx_k__lines), 0, 0, 1, 1},
   {&__pyx_n_s__name, __pyx_k__name, sizeof(__pyx_k__name), 0, 0, 1, 1},
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   {&__pyx_n_s__range, __pyx_k__range, sizeof(__pyx_k__range), 0, 0, 1, 1},
   {&__pyx_n_s__refs, __pyx_k__refs, sizeof(__pyx_k__refs), 0, 0, 1, 1},
+  {&__pyx_n_s__replace, __pyx_k__replace, sizeof(__pyx_k__replace), 0, 0, 1, 1},
   {&__pyx_n_s__self, __pyx_k__self, sizeof(__pyx_k__self), 0, 0, 1, 1},
   {&__pyx_n_s__sentence, __pyx_k__sentence, sizeof(__pyx_k__sentence), 0, 0, 1, 1},
   {&__pyx_n_s__split, __pyx_k__split, sizeof(__pyx_k__split), 0, 0, 1, 1},
   {&__pyx_n_s__strip, __pyx_k__strip, sizeof(__pyx_k__strip), 0, 0, 1, 1},
   {&__pyx_n_s__utf8, __pyx_k__utf8, sizeof(__pyx_k__utf8), 0, 0, 1, 1},
+  {&__pyx_n_s__weight, __pyx_k__weight, sizeof(__pyx_k__weight), 0, 0, 1, 1},
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 };
 static int __Pyx_InitCachedBuiltins(void) {
@@ -12659,7 +14187,7 @@ static int __Pyx_InitCachedBuiltins(void) {
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   __pyx_builtin_enumerate = __Pyx_GetName(__pyx_b, __pyx_n_s__enumerate); if (!__pyx_builtin_enumerate) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 9; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __pyx_builtin_IndexError = __Pyx_GetName(__pyx_b, __pyx_n_s__IndexError); if (!__pyx_builtin_IndexError) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 21; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_builtin_open = __Pyx_GetName(__pyx_b, __pyx_n_s__open); if (!__pyx_builtin_open) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 31; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_builtin_open = __Pyx_GetName(__pyx_b, __pyx_n_s__open); if (!__pyx_builtin_open) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 47; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   return 0;
   __pyx_L1_error:;
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@@ -12837,6 +14365,59 @@ static int __Pyx_InitCachedConstants(void) {
   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
   __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_18));
 
+  /* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":65
+ *             for i in range(len(self)):
+ *                 for label, weight, delta in self[i]:
+ *                     yield '%d -> %d [label="%s"];' % (i, i+delta, label.replace('"', '\\"'))             # <<<<<<<<<<<<<<
+ *             yield '%d [shape=doublecircle]' % len(self)
+ *             yield '}'
+ */
+  __pyx_k_tuple_25 = PyTuple_New(2); if (unlikely(!__pyx_k_tuple_25)) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 65; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_25);
+  __Pyx_INCREF(((PyObject *)__pyx_kp_s_23));
+  PyTuple_SET_ITEM(__pyx_k_tuple_25, 0, ((PyObject *)__pyx_kp_s_23));
+  __Pyx_GIVEREF(((PyObject *)__pyx_kp_s_23));
+  __Pyx_INCREF(((PyObject *)__pyx_kp_s_24));
+  PyTuple_SET_ITEM(__pyx_k_tuple_25, 1, ((PyObject *)__pyx_kp_s_24));
+  __Pyx_GIVEREF(((PyObject *)__pyx_kp_s_24));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_25));
+
+  /* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":59
+ * 
+ *     def todot(self):
+ *         def lines():             # <<<<<<<<<<<<<<
+ *             yield 'digraph lattice {'
+ *             yield 'rankdir = LR;'
+ */
+  __pyx_k_tuple_28 = PyTuple_New(4); if (unlikely(!__pyx_k_tuple_28)) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_28);
+  __Pyx_INCREF(((PyObject *)__pyx_n_s__i));
+  PyTuple_SET_ITEM(__pyx_k_tuple_28, 0, ((PyObject *)__pyx_n_s__i));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__i));
+  __Pyx_INCREF(((PyObject *)__pyx_n_s__label));
+  PyTuple_SET_ITEM(__pyx_k_tuple_28, 1, ((PyObject *)__pyx_n_s__label));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__label));
+  __Pyx_INCREF(((PyObject *)__pyx_n_s__weight));
+  PyTuple_SET_ITEM(__pyx_k_tuple_28, 2, ((PyObject *)__pyx_n_s__weight));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__weight));
+  __Pyx_INCREF(((PyObject *)__pyx_n_s__delta));
+  PyTuple_SET_ITEM(__pyx_k_tuple_28, 3, ((PyObject *)__pyx_n_s__delta));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__delta));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_28));
+  __pyx_k_codeobj_29 = (PyObject*)__Pyx_PyCode_New(0, 0, 4, 0, 0, __pyx_empty_bytes, __pyx_empty_tuple, __pyx_empty_tuple, __pyx_k_tuple_28, __pyx_empty_tuple, __pyx_empty_tuple, __pyx_kp_s_30, __pyx_n_s__lines, 59, __pyx_empty_bytes); if (unlikely(!__pyx_k_codeobj_29)) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+
+  /* "/Users/vchahun/Sandbox/cdec/python/src/lattice.pxi":68
+ *             yield '%d [shape=doublecircle]' % len(self)
+ *             yield '}'
+ *         return '\n'.join(lines()).encode('utf8')             # <<<<<<<<<<<<<<
+ */
+  __pyx_k_tuple_32 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_32)) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 68; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_32);
+  __Pyx_INCREF(((PyObject *)__pyx_n_s__utf8));
+  PyTuple_SET_ITEM(__pyx_k_tuple_32, 0, ((PyObject *)__pyx_n_s__utf8));
+  __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_32));
+
   /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":6
  *     cdef bytes ret
  *     if isinstance(sentence, unicode):
@@ -12844,85 +14425,85 @@ static int __Pyx_InitCachedConstants(void) {
  *     elif isinstance(sentence, str):
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-  __pyx_k_tuple_20 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_20)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 6; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __Pyx_GOTREF(__pyx_k_tuple_20);
+  __pyx_k_tuple_34 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_34)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 6; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_34);
   __Pyx_INCREF(((PyObject *)__pyx_n_s__utf8));
-  PyTuple_SET_ITEM(__pyx_k_tuple_20, 0, ((PyObject *)__pyx_n_s__utf8));
+  PyTuple_SET_ITEM(__pyx_k_tuple_34, 0, ((PyObject *)__pyx_n_s__utf8));
   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_20));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_34));
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":78
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":89
  *     def __getitem__(self,int k):
  *         if not 0 <= k < self.cs.size():
  *             raise IndexError('candidate set index out of range')             # <<<<<<<<<<<<<<
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-  __pyx_k_tuple_22 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_22)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 78; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __Pyx_GOTREF(__pyx_k_tuple_22);
-  __Pyx_INCREF(((PyObject *)__pyx_kp_s_21));
-  PyTuple_SET_ITEM(__pyx_k_tuple_22, 0, ((PyObject *)__pyx_kp_s_21));
-  __Pyx_GIVEREF(((PyObject *)__pyx_kp_s_21));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_22));
+  __pyx_k_tuple_36 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_36)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 89; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_36);
+  __Pyx_INCREF(((PyObject *)__pyx_kp_s_35));
+  PyTuple_SET_ITEM(__pyx_k_tuple_36, 0, ((PyObject *)__pyx_kp_s_35));
+  __Pyx_GIVEREF(((PyObject *)__pyx_kp_s_35));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_36));
 
-  /* "_cdec.pyx":31
+  /* "_cdec.pyx":47
  * 
  *     def read_weights(self, cfg):
  *         with open(cfg) as fp:             # <<<<<<<<<<<<<<
  *             for line in fp:
  *                 fname, value = line.split()
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-  __pyx_k_tuple_23 = PyTuple_New(3); if (unlikely(!__pyx_k_tuple_23)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 31; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __Pyx_GOTREF(__pyx_k_tuple_23);
+  __pyx_k_tuple_38 = PyTuple_New(3); if (unlikely(!__pyx_k_tuple_38)) {__pyx_filename = __pyx_f[0]; __pyx_lineno = 47; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_38);
   __Pyx_INCREF(Py_None);
-  PyTuple_SET_ITEM(__pyx_k_tuple_23, 0, Py_None);
+  PyTuple_SET_ITEM(__pyx_k_tuple_38, 0, Py_None);
   __Pyx_GIVEREF(Py_None);
   __Pyx_INCREF(Py_None);
-  PyTuple_SET_ITEM(__pyx_k_tuple_23, 1, Py_None);
+  PyTuple_SET_ITEM(__pyx_k_tuple_38, 1, Py_None);
   __Pyx_GIVEREF(Py_None);
   __Pyx_INCREF(Py_None);
-  PyTuple_SET_ITEM(__pyx_k_tuple_23, 2, Py_None);
+  PyTuple_SET_ITEM(__pyx_k_tuple_38, 2, Py_None);
   __Pyx_GIVEREF(Py_None);
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_23));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_38));
 
-  /* "_cdec.pyx":38
+  /* "_cdec.pyx":54
  *     def translate(self, sentence, grammar=None):
  *         if isinstance(sentence, unicode):
  *             inp = sentence.strip().encode('utf8')             # <<<<<<<<<<<<<<
  *         elif isinstance(sentence, str):
  *             inp = sentence.strip()
  */
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-  __Pyx_GOTREF(__pyx_k_tuple_24);
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   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__utf8));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_24));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_39));
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":142
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":153
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-  __Pyx_GOTREF(__pyx_k_tuple_26);
+  __pyx_k_tuple_41 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_41)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 153; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_41);
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-  PyTuple_SET_ITEM(__pyx_k_tuple_26, 0, ((PyObject *)__pyx_n_s__IBM_BLEU));
+  PyTuple_SET_ITEM(__pyx_k_tuple_41, 0, ((PyObject *)__pyx_n_s__IBM_BLEU));
   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__IBM_BLEU));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_26));
+  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_41));
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":143
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":154
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  * TER = Scorer('TER')             # <<<<<<<<<<<<<<
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-  __pyx_k_tuple_27 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_27)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 143; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __Pyx_GOTREF(__pyx_k_tuple_27);
+  __pyx_k_tuple_42 = PyTuple_New(1); if (unlikely(!__pyx_k_tuple_42)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 154; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __Pyx_GOTREF(__pyx_k_tuple_42);
   __Pyx_INCREF(((PyObject *)__pyx_n_s__TER));
-  PyTuple_SET_ITEM(__pyx_k_tuple_27, 0, ((PyObject *)__pyx_n_s__TER));
+  PyTuple_SET_ITEM(__pyx_k_tuple_42, 0, ((PyObject *)__pyx_n_s__TER));
   __Pyx_GIVEREF(((PyObject *)__pyx_n_s__TER));
-  __Pyx_GIVEREF(((PyObject *)__pyx_k_tuple_27));
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@@ -13018,20 +14599,20 @@ PyMODINIT_FUNC PyInit__cdec(void)
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   if (__Pyx_SetAttrString(__pyx_m, "Lattice", (PyObject *)&__pyx_type_5_cdec_Lattice) < 0) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 3; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  if (PyType_Ready(&__pyx_type_5_cdec_Candidate) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  if (__Pyx_SetAttrString(__pyx_m, "Candidate", (PyObject *)&__pyx_type_5_cdec_Candidate) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 13; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyType_Ready(&__pyx_type_5_cdec_Candidate) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 22; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (__Pyx_SetAttrString(__pyx_m, "Candidate", (PyObject *)&__pyx_type_5_cdec_Candidate) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 22; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  if (PyType_Ready(&__pyx_type_5_cdec_SufficientStats) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 27; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  if (__Pyx_SetAttrString(__pyx_m, "SufficientStats", (PyObject *)&__pyx_type_5_cdec_SufficientStats) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 27; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyType_Ready(&__pyx_type_5_cdec_SufficientStats) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 36; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (__Pyx_SetAttrString(__pyx_m, "SufficientStats", (PyObject *)&__pyx_type_5_cdec_SufficientStats) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 36; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  if (PyType_Ready(&__pyx_type_5_cdec_CandidateSet) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  if (__Pyx_SetAttrString(__pyx_m, "CandidateSet", (PyObject *)&__pyx_type_5_cdec_CandidateSet) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyType_Ready(&__pyx_type_5_cdec_CandidateSet) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 70; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (__Pyx_SetAttrString(__pyx_m, "CandidateSet", (PyObject *)&__pyx_type_5_cdec_CandidateSet) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 70; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  if (PyType_Ready(&__pyx_type_5_cdec_SegmentEvaluator) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 92; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  if (__Pyx_SetAttrString(__pyx_m, "SegmentEvaluator", (PyObject *)&__pyx_type_5_cdec_SegmentEvaluator) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 92; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyType_Ready(&__pyx_type_5_cdec_SegmentEvaluator) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 103; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (__Pyx_SetAttrString(__pyx_m, "SegmentEvaluator", (PyObject *)&__pyx_type_5_cdec_SegmentEvaluator) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 103; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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-  if (__Pyx_SetAttrString(__pyx_m, "Scorer", (PyObject *)&__pyx_type_5_cdec_Scorer) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 111; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (PyType_Ready(&__pyx_type_5_cdec_Scorer) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 122; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  if (__Pyx_SetAttrString(__pyx_m, "Scorer", (PyObject *)&__pyx_type_5_cdec_Scorer) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 122; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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@@ -13050,34 +14631,38 @@ PyMODINIT_FUNC PyInit__cdec(void)
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-  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_7___iter__) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 45; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
-  __pyx_ptype_5_cdec___pyx_scope_struct_7___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_7___iter__;
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-  __pyx_ptype_5_cdec___pyx_scope_struct_8___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_8___iter__;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_7_todot) < 0) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 58; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_7_todot = &__pyx_type_5_cdec___pyx_scope_struct_7_todot;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_8_lines) < 0) {__pyx_filename = __pyx_f[3]; __pyx_lineno = 59; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_8_lines = &__pyx_type_5_cdec___pyx_scope_struct_8_lines;
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+  __pyx_ptype_5_cdec___pyx_scope_struct_9___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_9___iter__;
+  if (PyType_Ready(&__pyx_type_5_cdec___pyx_scope_struct_10___iter__) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 95; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
+  __pyx_ptype_5_cdec___pyx_scope_struct_10___iter__ = &__pyx_type_5_cdec___pyx_scope_struct_10___iter__;
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   /*--- Function import code ---*/
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-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":142
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+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Scorer)), ((PyObject *)__pyx_k_tuple_41), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 153; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__BLEU, __pyx_t_1) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 153; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
   __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
 
-  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":143
+  /* "/Users/vchahun/Sandbox/cdec/python/src/mteval.pxi":154
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+  __pyx_t_1 = PyObject_Call(((PyObject *)((PyObject*)__pyx_ptype_5_cdec_Scorer)), ((PyObject *)__pyx_k_tuple_42), NULL); if (unlikely(!__pyx_t_1)) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 154; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+  if (PyObject_SetAttr(__pyx_m, __pyx_n_s__TER, __pyx_t_1) < 0) {__pyx_filename = __pyx_f[4]; __pyx_lineno = 154; __pyx_clineno = __LINE__; goto __pyx_L1_error;}
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+        op->func_doc = value;
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+        op->func_name = PyUnicode_InternFromString(op->func.m_ml->ml_name);
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+{
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+    {(char *) "__code__", (getter)__Pyx_CyFunction_get_code, 0, 0, 0},
+    {(char *) "func_defaults", (getter)__Pyx_CyFunction_get_defaults, 0, 0, 0},
+    {(char *) "__defaults__", (getter)__Pyx_CyFunction_get_defaults, 0, 0, 0},
+    {0, 0, 0, 0, 0}
+};
+#ifndef PY_WRITE_RESTRICTED /* < Py2.5 */
+#define PY_WRITE_RESTRICTED WRITE_RESTRICTED
+#endif
+static PyMemberDef __pyx_CyFunction_members[] = {
+    {(char *) "__module__", T_OBJECT, offsetof(__pyx_CyFunctionObject, func.m_module), PY_WRITE_RESTRICTED, 0},
+    {0, 0, 0,  0, 0}
+};
+static PyObject *
+__Pyx_CyFunction_reduce(__pyx_CyFunctionObject *m, CYTHON_UNUSED PyObject *args)
+{
+#if PY_MAJOR_VERSION >= 3
+    return PyUnicode_FromString(m->func.m_ml->ml_name);
+#else
+    return PyString_FromString(m->func.m_ml->ml_name);
+#endif
+}
+static PyMethodDef __pyx_CyFunction_methods[] = {
+    {__Pyx_NAMESTR("__reduce__"), (PyCFunction)__Pyx_CyFunction_reduce, METH_VARARGS, 0},
+    {0, 0, 0, 0}
+};
+static PyObject *__Pyx_CyFunction_New(PyTypeObject *type, PyMethodDef *ml, int flags,
+                                      PyObject *closure, PyObject *module, PyObject* code) {
+    __pyx_CyFunctionObject *op = PyObject_GC_New(__pyx_CyFunctionObject, type);
+    if (op == NULL)
+        return NULL;
+    op->flags = flags;
+    op->func_weakreflist = NULL;
+    op->func.m_ml = ml;
+    op->func.m_self = (PyObject *) op;
+    Py_XINCREF(closure);
+    op->func_closure = closure;
+    Py_XINCREF(module);
+    op->func.m_module = module;
+    op->func_dict = NULL;
+    op->func_name = NULL;
+    op->func_doc = NULL;
+    op->func_classobj = NULL;
+    Py_XINCREF(code);
+    op->func_code = code;
+    op->defaults_pyobjects = 0;
+    op->defaults = NULL;
+    op->defaults_tuple = NULL;
+    op->defaults_getter = NULL;
+    PyObject_GC_Track(op);
+    return (PyObject *) op;
+}
+static int
+__Pyx_CyFunction_clear(__pyx_CyFunctionObject *m)
+{
+    Py_CLEAR(m->func_closure);
+    Py_CLEAR(m->func.m_module);
+    Py_CLEAR(m->func_dict);
+    Py_CLEAR(m->func_name);
+    Py_CLEAR(m->func_doc);
+    Py_CLEAR(m->func_code);
+    Py_CLEAR(m->func_classobj);
+    Py_CLEAR(m->defaults_tuple);
+    if (m->defaults) {
+        PyObject **pydefaults = __Pyx_CyFunction_Defaults(PyObject *, m);
+        int i;
+        for (i = 0; i < m->defaults_pyobjects; i++)
+            Py_XDECREF(pydefaults[i]);
+        PyMem_Free(m->defaults);
+        m->defaults = NULL;
+    }
+    return 0;
+}
+static void __Pyx_CyFunction_dealloc(__pyx_CyFunctionObject *m)
+{
+    PyObject_GC_UnTrack(m);
+    if (m->func_weakreflist != NULL)
+        PyObject_ClearWeakRefs((PyObject *) m);
+    __Pyx_CyFunction_clear(m);
+    PyObject_GC_Del(m);
+}
+static int __Pyx_CyFunction_traverse(__pyx_CyFunctionObject *m, visitproc visit, void *arg)
+{
+    Py_VISIT(m->func_closure);
+    Py_VISIT(m->func.m_module);
+    Py_VISIT(m->func_dict);
+    Py_VISIT(m->func_name);
+    Py_VISIT(m->func_doc);
+    Py_VISIT(m->func_code);
+    Py_VISIT(m->func_classobj);
+    Py_VISIT(m->defaults_tuple);
+    if (m->defaults) {
+        PyObject **pydefaults = __Pyx_CyFunction_Defaults(PyObject *, m);
+        int i;
+        for (i = 0; i < m->defaults_pyobjects; i++)
+            Py_VISIT(pydefaults[i]);
+    }
+    return 0;
+}
+static PyObject *__Pyx_CyFunction_descr_get(PyObject *func, PyObject *obj, PyObject *type)
+{
+    __pyx_CyFunctionObject *m = (__pyx_CyFunctionObject *) func;
+    if (m->flags & __Pyx_CYFUNCTION_STATICMETHOD) {
+        Py_INCREF(func);
+        return func;
+    }
+    if (m->flags & __Pyx_CYFUNCTION_CLASSMETHOD) {
+        if (type == NULL)
+            type = (PyObject *)(Py_TYPE(obj));
+        return PyMethod_New(func,
+                            type, (PyObject *)(Py_TYPE(type)));
+    }
+    if (obj == Py_None)
+        obj = NULL;
+    return PyMethod_New(func, obj, type);
+}
+static PyObject*
+__Pyx_CyFunction_repr(__pyx_CyFunctionObject *op)
+{
+    PyObject *func_name = __Pyx_CyFunction_get_name(op);
+#if PY_MAJOR_VERSION >= 3
+    return PyUnicode_FromFormat("<cyfunction %U at %p>",
+                                func_name, (void *)op);
+#else
+    return PyString_FromFormat("<cyfunction %s at %p>",
+                               PyString_AsString(func_name), (void *)op);
+#endif
+}
+static PyTypeObject __pyx_CyFunctionType_type = {
+    PyVarObject_HEAD_INIT(0, 0)
+    __Pyx_NAMESTR("cython_function_or_method"), /*tp_name*/
+    sizeof(__pyx_CyFunctionObject),   /*tp_basicsize*/
+    0,                                  /*tp_itemsize*/
+    (destructor) __Pyx_CyFunction_dealloc, /*tp_dealloc*/
+    0,                                  /*tp_print*/
+    0,                                  /*tp_getattr*/
+    0,                                  /*tp_setattr*/
+#if PY_MAJOR_VERSION < 3
+    0,                                  /*tp_compare*/
+#else
+    0,                                  /*reserved*/
+#endif
+    (reprfunc) __Pyx_CyFunction_repr,   /*tp_repr*/
+    0,                                  /*tp_as_number*/
+    0,                                  /*tp_as_sequence*/
+    0,                                  /*tp_as_mapping*/
+    0,                                  /*tp_hash*/
+    __Pyx_PyCFunction_Call,             /*tp_call*/
+    0,                                  /*tp_str*/
+    0,                                  /*tp_getattro*/
+    0,                                  /*tp_setattro*/
+    0,                                  /*tp_as_buffer*/
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, /* tp_flags*/
+    0,                                  /*tp_doc*/
+    (traverseproc) __Pyx_CyFunction_traverse,   /*tp_traverse*/
+    (inquiry) __Pyx_CyFunction_clear,   /*tp_clear*/
+    0,                                  /*tp_richcompare*/
+    offsetof(__pyx_CyFunctionObject, func_weakreflist), /* tp_weaklistoffse */
+    0,                                  /*tp_iter*/
+    0,                                  /*tp_iternext*/
+    __pyx_CyFunction_methods,           /*tp_methods*/
+    __pyx_CyFunction_members,           /*tp_members*/
+    __pyx_CyFunction_getsets,           /*tp_getset*/
+    0,                                  /*tp_base*/
+    0,                                  /*tp_dict*/
+    __Pyx_CyFunction_descr_get,         /*tp_descr_get*/
+    0,                                  /*tp_descr_set*/
+    offsetof(__pyx_CyFunctionObject, func_dict),/*tp_dictoffset*/
+    0,                                  /*tp_init*/
+    0,                                  /*tp_alloc*/
+    0,                                  /*tp_new*/
+    0,                                  /*tp_free*/
+    0,                                  /*tp_is_gc*/
+    0,                                  /*tp_bases*/
+    0,                                  /*tp_mro*/
+    0,                                  /*tp_cache*/
+    0,                                  /*tp_subclasses*/
+    0,                                  /*tp_weaklist*/
+    0,                                  /*tp_del*/
+#if PY_VERSION_HEX >= 0x02060000
+    0,                                  /*tp_version_tag*/
+#endif
+};
+static int __Pyx_CyFunction_init(void)
+{
+    if (PyType_Ready(&__pyx_CyFunctionType_type) < 0)
+        return -1;
+    __pyx_CyFunctionType = &__pyx_CyFunctionType_type;
+    return 0;
+}
+void *__Pyx_CyFunction_InitDefaults(PyObject *func, size_t size, int pyobjects)
+{
+    __pyx_CyFunctionObject *m = (__pyx_CyFunctionObject *) func;
+    m->defaults = PyMem_Malloc(size);
+    if (!m->defaults)
+        return PyErr_NoMemory();
+    memset(m->defaults, 0, sizeof(size));
+    m->defaults_pyobjects = pyobjects;
+    return m->defaults;
+}
+static void __Pyx_CyFunction_SetDefaultsTuple(PyObject *func, PyObject *tuple)
+{
+    __pyx_CyFunctionObject *m = (__pyx_CyFunctionObject *) func;
+    m->defaults_tuple = tuple;
+    Py_INCREF(tuple);
+}
+
 static CYTHON_INLINE unsigned char __Pyx_PyInt_AsUnsignedChar(PyObject* x) {
     const unsigned char neg_one = (unsigned char)-1, const_zero = 0;
     const int is_unsigned = neg_one > const_zero;
diff --git a/python/src/_cdec.pyx b/python/src/_cdec.pyx
index 6fafbbc0..cccfec0b 100644
--- a/python/src/_cdec.pyx
+++ b/python/src/_cdec.pyx
@@ -14,7 +14,7 @@ class ParseFailed(Exception): pass
 
 cdef class Decoder:
     cdef decoder.Decoder* dec
-    cdef public DenseVector weights
+    cdef DenseVector weights
 
     def __cinit__(self, char* config):
         decoder.register_feature_functions()
@@ -27,6 +27,22 @@ cdef class Decoder:
     def __dealloc__(self):
         del self.dec
 
+    property weights:
+        def __get__(self):
+            return self.weights
+
+        def __set__(self, weights):
+            if isinstance(weights, DenseVector):
+                self.weights.vector[0] = (<DenseVector> weights).vector[0]
+            elif isinstance(weights, SparseVector):
+                self.weights.vector.clear()
+                ((<SparseVector> weights).vector[0]).init_vector(self.weights.vector)
+            elif isinstance(weights, dict):
+                for fname, fval in weights.items():
+                    self.weights[fname] = fval
+            else:
+                raise TypeError('cannot initialize weights with %s' % type(weights))
+
     def read_weights(self, cfg):
         with open(cfg) as fp:
             for line in fp:
diff --git a/python/src/lattice.pxi b/python/src/lattice.pxi
index 493c6dcd..f8341e29 100644
--- a/python/src/lattice.pxi
+++ b/python/src/lattice.pxi
@@ -54,3 +54,15 @@ cdef class Lattice:
 
     def __dealloc__(self):
         del self.lattice
+
+    def todot(self):
+        def lines():
+            yield 'digraph lattice {'
+            yield 'rankdir = LR;'
+            yield 'node [shape=circle];'
+            for i in range(len(self)):
+                for label, weight, delta in self[i]:
+                    yield '%d -> %d [label="%s"];' % (i, i+delta, label.replace('"', '\\"'))
+            yield '%d [shape=doublecircle]' % len(self)
+            yield '}'
+        return '\n'.join(lines()).encode('utf8')
diff --git a/python/src/mteval.pxi b/python/src/mteval.pxi
index 67a29f6f..d90eb9a6 100644
--- a/python/src/mteval.pxi
+++ b/python/src/mteval.pxi
@@ -10,6 +10,15 @@ cdef char* as_str(sentence, error_msg='Cannot convert type %s to str'):
         raise TypeError(error_msg % type(sentence))
     return ret
 
+cdef SufficientStats as_stats(x, y):
+    if isinstance(x, SufficientStats):
+        return x
+    elif x == 0 and isinstance(y, SufficientStats):
+        stats = SufficientStats()
+        stats.stats = new mteval.SufficientStats()
+        stats.metric = (<SufficientStats> y).metric
+        return stats
+
 cdef class Candidate:
     cdef mteval.Candidate* candidate
     cdef public float score
@@ -50,10 +59,12 @@ cdef class SufficientStats:
         self.stats[0] += other.stats[0]
         return self
 
-    def __add__(SufficientStats x, SufficientStats y):
+    def __add__(x, y):
+        cdef SufficientStats sx = as_stats(x, y)
+        cdef SufficientStats sy = as_stats(y, x)
         cdef SufficientStats result = SufficientStats()
-        result.stats = new mteval.SufficientStats(mteval.add(x.stats[0], y.stats[0]))
-        result.metric = x.metric
+        result.stats = new mteval.SufficientStats(mteval.add(sx.stats[0], sy.stats[0]))
+        result.metric = sx.metric
         return result
 
 cdef class CandidateSet:
diff --git a/python/src/vectors.pxi b/python/src/vectors.pxi
index fc0c365f..ce95968c 100644
--- a/python/src/vectors.pxi
+++ b/python/src/vectors.pxi
@@ -80,6 +80,12 @@ cdef class SparseVector:
 
     def __contains__(self, char* fname):
         return self.vector.nonzero(FDConvert(fname))
+
+    def __neg__(self):
+        cdef SparseVector result = SparseVector()
+        result.vector = new FastSparseVector[weight_t](self.vector[0])
+        result.vector[0] *= -1.0
+        return result
     
     def __iadd__(SparseVector self, SparseVector other):
         self.vector[0] += other.vector[0]