fix auc

Author: jacquesqiao

python/paddle/fluid/metrics.py

@@ -325,14 +325,14 @@ class Auc(MetricBase):
     """
 
     def __init__(self, name, curve='ROC', num_thresholds=200):
-        super(MetricBase, self).__init__(name, curve, num_thresholds)
+        super(Auc, self).__init__(name=name)
         self._curve = curve
         self._num_thresholds = num_thresholds
         self._epsilon = 1e-6
-        self.tp_list = np.ndarray((num_thresholds, ))
-        self.fn_list = np.ndarray((num_thresholds, ))
-        self.tn_list = np.ndarray((num_thresholds, ))
-        self.fp_list = np.ndarray((num_thresholds, ))
+        self.tp_list = np.zeros((num_thresholds, ))
+        self.fn_list = np.zeros((num_thresholds, ))
+        self.tn_list = np.zeros((num_thresholds, ))
+        self.fp_list = np.zeros((num_thresholds, ))
 
     def update(self, labels, predictions, axis=1):
         if not _is_numpy_(labels):
@@ -350,12 +350,12 @@ def update(self, labels, predictions, axis=1):
             tp, fn, tn, fp = 0, 0, 0, 0
             for i, lbl in enumerate(labels):
                 if lbl:
-                    if predictions[i, 0] >= thresh:
+                    if predictions[i, 1] >= thresh:
                         tp += 1
                     else:
                         fn += 1
                 else:
-                    if predictions[i, 0] >= thresh:
+                    if predictions[i, 1] >= thresh:
                         fp += 1
                     else:
                         tn += 1