Pool layer problem

[ZFTurbo]

I think you have error in _pool_backward function at this place:

dX = dpool_fun(dX_col, dout_col, pool_cache)

You set dX which is not used later.

UPD: IT actually not critical since dX_col is changed internally. So this line can be changed on:

dpool_fun(dX_col, dout_col, pool_cache)

or

dX_col= dpool_fun(dX_col, dout_col, pool_cache)