Dropout on sparse input

The mx.symbol.sparse package does not support adding a Dropout layer on a sparse input. Well, technically, it does, but the input is being converted to a dense representation slowing down training considerably.

Is there a reason this is not supported? Any alternatives?

Yes, dropouts are currently not supported yet by the mx.symbol.sparse package. In order to avoid the conversion, you could create your own operator https://github.com/apache/incubator-mxnet/blob/master/example/numpy-ops/custom_sparse_sqr.py#L22-L36

Thanks. I’ll give that a shot.