sample trees from hypergraphs

2 files changed, 16 insertions, 0 deletions

diff --git a/python/src/hypergraph.pxd b/python/src/hypergraph.pxd
index 886660bf..abd6759c 100644
--- a/python/src/hypergraph.pxd
+++ b/python/src/hypergraph.pxd
@@ -76,6 +76,10 @@ cdef extern from "decoder/hg_sampler.h" namespace "HypergraphSampler":
                            unsigned n, 
                            MT19937* rng, 
                            vector[Hypothesis]* hypos)
+    void sample_trees(Hypergraph& hg, 
+                      unsigned n, 
+                      MT19937* rng, 
+                      vector[string]* trees)
 
 cdef extern from "decoder/csplit.h" namespace "CompoundSplit":
     int GetFullWordEdgeIndex(Hypergraph& forest)
diff --git a/python/src/hypergraph.pxi b/python/src/hypergraph.pxi
index b210f440..62dd5bb1 100644
--- a/python/src/hypergraph.pxi
+++ b/python/src/hypergraph.pxi
@@ -85,6 +85,18 @@ cdef class Hypergraph:
         finally:
             del hypos
 
+    def sample_trees(self, unsigned n):
+       cdef vector[string]* trees = new vector[string]()
+       if self.rng == NULL:
+           self.rng = new MT19937()
+       hypergraph.sample_trees(self.hg[0], n, self.rng, trees)
+       cdef unsigned k
+       try:
+           for k in range(trees.size()):
+               yield unicode(trees[0][k].c_str(), 'utf8')
+       finally:
+           del trees
+
     def intersect(self, Lattice lat):
         return hypergraph.Intersect(lat.lattice[0], self.hg)