A question about fc_op in FullyConLayer.py

[kid09321]

Hi, As title, fc_op function in FullyConLayer.py.

val = exp((4.0/3)*val)
self.maps[0][0][node_index] = 1.7159 *  (val -1) / (val + 1)

Could you explain why val should times 4.0/3 and how to get the (val-1)/(val+1)? Thanks a lot.