3 files changed, 26 insertions, 2 deletions

diff --git a/src/storage/flexible_ngram.h b/src/storage/flexible_ngram.h
index 0141367..3fa452d 100644
--- a/src/storage/flexible_ngram.h
+++ b/src/storage/flexible_ngram.h
@@ -325,6 +325,19 @@ public:
         return ret == 0;
     }
 
+    bool remove(phrase_token_t index){
+        if ( !m_db )
+            return false;
+
+        DBT db_key;
+        memset(&db_key, 0, sizeof(DBT));
+        db_key.data = &index;
+        db_key.size = sizeof(phrase_token_t);
+
+        int ret = m_db->del(m_db, NULL, &db_key, 0);
+        return ret == 0;
+    }
+
     /* array of phrase_token_t items, for parameter estimation. */
     bool get_all_items(GArray * items){
         g_array_set_size(items, 0);
diff --git a/tests/storage/test_flexible_ngram.cpp b/tests/storage/test_flexible_ngram.cpp
index ea17adb..4e48715 100644
--- a/tests/storage/test_flexible_ngram.cpp
+++ b/tests/storage/test_flexible_ngram.cpp
@@ -61,7 +61,7 @@ int main(int argc, char * argv[]) {
 
     GArray * items = g_array_new(FALSE, FALSE, sizeof(phrase_token_t));
     bigram.get_all_items(items);
-    printf("-----------------------train----------------------------\n");
+    printf("-----------------------items----------------------------\n");
     for ( size_t i = 0; i < items->len; ++i ){
         phrase_token_t * token = &g_array_index(items, phrase_token_t, i);
         printf("item:%d\n", *token);
@@ -101,6 +101,16 @@ int main(int argc, char * argv[]) {
         delete train_gram;
     }
 
+    assert(bigram.remove(1));
+
+    bigram.get_all_items(items);
+    printf("-----------------------items----------------------------\n");
+    for ( size_t i = 0; i < items->len; ++i ){
+        phrase_token_t * token = &g_array_index(items, phrase_token_t, i);
+        printf("item:%d\n", *token);
+    }
+
+    g_array_free(items, TRUE);
     g_array_free(array, TRUE);
     return 0;
 }
diff --git a/utils/training/estimate_k_mixture_model.cpp b/utils/training/estimate_k_mixture_model.cpp
index 6399281..88452d1 100644
--- a/utils/training/estimate_k_mixture_model.cpp
+++ b/utils/training/estimate_k_mixture_model.cpp
@@ -8,7 +8,7 @@ parameter_t compute_interpolation(KMixtureModelSingleGram * deleted_bigram,
     parameter_t lambda = 0, next_lambda = 0.6;
     parameter_t epsilon = 0.001;
 
-    while ( fabs(lambda - next_lambda) > epsilon){
+    while (fabs(lambda - next_lambda) > epsilon){
         lambda = next_lambda;
         next_lambda = 0;
         parameter_t numerator = 0;
@@ -54,6 +54,7 @@ parameter_t compute_interpolation(KMixtureModelSingleGram * deleted_bigram,
         }
         KMixtureModelArrayHeader header;
         assert(deleted_bigram->get_array_header(header));
+        assert(0 != header.m_WC);
         next_lambda /= header.m_WC;
 
         g_array_free(array, TRUE);