fix llh

git-svn-id: https://ws10smt.googlecode.com/svn/trunk@633 ec762483-ff6d-05da-a07a-a48fb63a330f

1 files changed, 21 insertions, 12 deletions

diff --git a/gi/clda/src/ccrp.h b/gi/clda/src/ccrp.h
index 74d5be29..a7c2825c 100644
--- a/gi/clda/src/ccrp.h
+++ b/gi/clda/src/ccrp.h
@@ -12,8 +12,7 @@
 #include "sampler.h"
 #include "slice_sampler.h"
 
-// Chinese restaurant process (Pitman-Yor parameters) with explicit table
-// tracking.
+// Chinese restaurant process (Pitman-Yor parameters) with table tracking.
 
 template <typename Dish, typename DishHash = boost::hash<Dish> >
 class CCRP {
@@ -65,6 +64,12 @@ class CCRP {
     return num_customers_;
   }
 
+  unsigned num_customers(const Dish& dish) const {
+    const typename std::tr1::unordered_map<Dish, DishLocations, DishHash>::const_iterator it = dish_locs_.find(dish);
+    if (it == dish_locs_.end()) return 0;
+    return it->total_dish_count_;
+  }
+
   // returns +1 or 0 indicating whether a new table was opened
   int increment(const Dish& dish, const double& p0, MT19937* rng) {
     DishLocations& loc = dish_locs_[dish];
@@ -177,17 +182,21 @@ class CCRP {
       lp += log_gamma_density(concentration, concentration_prior_shape_, concentration_prior_rate_);
     assert(lp <= 0.0);
     if (num_customers_) {
-      const double r = lgamma(1.0 - discount);
-      lp += lgamma(concentration) - lgamma(concentration + num_customers_)
-           + num_tables_ * discount + lgamma(concentration / discount + num_tables_)
-           - lgamma(concentration / discount);
-      assert(std::isfinite(lp));
-      for (typename std::tr1::unordered_map<Dish, DishLocations, DishHash>::const_iterator it = dish_locs_.begin();
-           it != dish_locs_.end(); ++it) {
-        const DishLocations& cur = it->second;
-        for (std::list<unsigned>::const_iterator ti = cur.table_counts_.begin(); ti != cur.table_counts_.end(); ++ti) {
-          lp += lgamma(*ti - discount) - r;
+      if (discount > 0.0) {
+        const double r = lgamma(1.0 - discount);
+        lp += lgamma(concentration) - lgamma(concentration + num_customers_)
+             + num_tables_ * log(discount) + lgamma(concentration / discount + num_tables_)
+             - lgamma(concentration / discount);
+        assert(std::isfinite(lp));
+        for (typename std::tr1::unordered_map<Dish, DishLocations, DishHash>::const_iterator it = dish_locs_.begin();
+             it != dish_locs_.end(); ++it) {
+          const DishLocations& cur = it->second;
+          for (std::list<unsigned>::const_iterator ti = cur.table_counts_.begin(); ti != cur.table_counts_.end(); ++ti) {
+            lp += lgamma(*ti - discount) - r;
+          }
         }
+      } else {
+        assert(!"not implemented yet");
       }
     }
     assert(std::isfinite(lp));