New operator defined with mshadow

[yijiezh]

The documentation of mshadow said mshadow is mainly for element-wise operation and using Map() when user defined a new operator.

Is this a strict requirement?
For example, is it possible to implement operation like concatenate with mshadow ?

[szha]

This code base has been donated to the Apache MXNet project per #373, and repo is deprecated. Future development and issue tracking should continue in Apache MXNet.