About error "more than one element of the written-to tensor refers to a single memory location."
Got it…so the +a created a tensor with a shape same as the target (3x3), while the other one relies on the expand_as().clone() to create a tensor of same shape. Thanks for the prompt help
https://discuss.pytorch.org/t/about-error-more-than-one-element-of-the-written-to-tensor-refers-to-a-single-memory-location/85526/3