1 files changed, 4 insertions, 0 deletions
diff --git a/spellchecker/src/SpellCorrector.java b/spellchecker/src/SpellCorrector.java
index f3e504d..875213f 100644
--- a/spellchecker/src/SpellCorrector.java
+++ b/spellchecker/src/SpellCorrector.java
@@ -13,6 +13,7 @@ public class SpellCorrector {
 
     /**
      * The highest n-gram to look for. 1 gives a unigram, 2 gives a bigram, etc.
+     * Be sure that the CorupusReader actually provide such many details!
      */
     private final static int NGRAM_N = 2;
 
@@ -335,6 +336,9 @@ public class SpellCorrector {
                 }
                 p *= score;
             }
+            // this can happen if probability_non_word or
+            // LM_PROBABILITY_UNMODIFIED are badly chosen (too small).
+            assert p > 0 : "The combined probabilities were too small";
             return p;
         }