Add Group Normalization

mindspore/nn/layer/normalization.py

@@ -346,7 +346,7 @@ class GroupNorm(Cell):
         self.sqrt = P.Sqrt()
 
     def construct(self, x):
-        batch, channel, height,width = self.shape(x)
+        batch, channel, height, width = self.shape(x)
         x = self.reshape(x, (batch, self.num_groups, channel*height*width/self.num_groups))
         mean = self.reduce_mean(x, 2)
         var = self.reduce_sum(self.square(x - mean), 2) / (channel * height * width / self.num_groups - 1)
@@ -359,4 +359,4 @@ class GroupNorm(Cell):
     def extend_repr(self):
         """Display instance object as string."""
         s = 'num_groups={}, num_channels={}'.format(self.num_groups, self.num_channels)
-        return s
\ No newline at end of file
+        return s

tests/ut/python/nn/test_batchnorm.py

@@ -67,4 +67,4 @@ class GroupNet(nn.Cell):
 def test_compile_groupnorm():
     net = nn.GroupNorm(16, 64)
     input_data = Tensor(np.random.rand(1,64,256,256).astype(np.float32))
-    _executor.compile(net, input_data)
\ No newline at end of file
+    _executor.compile(net, input_data)