message: use abs instead of cast
diff: @@ -558,9 +558,7 @@ def norm(tensor,
  permed = array_ops.transpose(tensor, perm=perm_before)
  matrix_2_norm = array_ops.expand_dims(
  math_ops.reduce_max(
  - math_ops.cast(
  - gen_linalg_ops.svd(permed, compute_uv=False)[0],
  - dtype=dtypes.float32),
  + math_ops.abs(gen_linalg_ops.svd(permed, compute_uv=False)[0]),
  axis=-1,
  keepdims=True),
  axis=-1)
  