Increase the max_relative_error in TestConv2dOp.

Author: hedaoyuan

python/paddle/v2/framework/tests/test_conv2d_op.py

@@ -73,13 +73,22 @@ def test_check_output(self):
         self.check_output()
 
     def test_check_grad(self):
-        self.check_grad(set(['Input', 'Filter']), 'Output')
+        self.check_grad(
+            set(['Input', 'Filter']), 'Output', max_relative_error=0.05)
 
     def test_check_grad_no_filter(self):
-        self.check_grad(['Input'], 'Output', no_grad_set=set(['Filter']))
+        self.check_grad(
+            ['Input'],
+            'Output',
+            max_relative_error=0.05,
+            no_grad_set=set(['Filter']))
 
     def test_check_grad_no_input(self):
-        self.check_grad(['Filter'], 'Output', no_grad_set=set(['Input']))
+        self.check_grad(
+            ['Filter'],
+            'Output',
+            max_relative_error=0.05,
+            no_grad_set=set(['Input']))
 
     def init_groups(self):
         self.groups = 1