title: RuntimeError: The expanded size of the tensor (7) must match the existing size (128) at non-singleton dimension 3
body: <p>When I run AdaIN code</p>
  <pre><code>def adaptive_instance_normalization(content_feat, style_mean, style_std):
      size = content_feat.size()
      content_mean, content_std = calc_mean_std(content_feat)
  
      normalized_feat = (content_feat - content_mean.expand(
          size)) / content_std.expand(size)
      return normalized_feat * style_std.expand(size) + style_mean.expand(size)
  </code></pre>
  <p>I got the following error</p>
  <p>RuntimeError: The expanded size of the tensor (7) must match the existing size (128) at non-singleton dimension 3.  Target sizes: [100, 128, 7, 7].  Tensor sizes: [100, 128]</p>