Revert "ENH: avoid an underflow"

GaelVaroquaux · GaelVaroquaux · commit 5b29e82a05c0 · 2012-05-06T23:26:30.000+02:00
That was a bad idea: this underflow is happening because there is only onlyone class This reverts commit 65abbb6.
diff --git a/sklearn/naive_bayes.py b/sklearn/naive_bayes.py
@@ -266,9 +266,7 @@ def fit(self, X, y, sample_weight=None, class_prior=None):
         elif self.fit_prior:
             # empirical prior, with sample_weight taken into account
             y_freq = Y.sum(axis=0)
-            eps = np.finfo(1.).eps
-            self.class_log_prior_ = (np.log(y_freq + eps)
-                                    - np.log(y_freq.sum() + eps))
+            self.class_log_prior_ = np.log(y_freq) - np.log(y_freq.sum())
         else:
             self.class_log_prior_ = np.zeros(n_classes) - np.log(n_classes)
 
