Speed up NN with tanh by not calling tanh(x), but an identical expression containing only exp(x).
Speed up NN with tanh by not calling tanh(x), but an identical expression
containing only exp(x).

This speeds up a single-layer NN using tanh by 33%.

100star/h2o,111t8e/h2o-2,eg-zhang/h2o-2,calvingit21/h2o-2,111t8e/h2o-2,h2oai/h2o-2,vbelakov/h2o,eg-zhang/h2o-2,calvingit21/h2o-2,calvingit21/h2o-2,elkingtonmcb/h2o-2,h2oai/h2o,100star/h2o,eg-zhang/h2o-2,eg-zhang/h2o-2,elkingtonmcb/h2o-2,calvingit21/h2o-2,vbelakov/h2o,calvingit21/h2o-2,100star/h2o,h2oai/h2o-2,h2oai/h2o,100star/h2o,100star/h2o,rowhit/h2o-2,111t8e/h2o-2,111t8e/h2o-2,h2oai/h2o,100star/h2o,111t8e/h2o-2,100star/h2o,h2oai/h2o-2,h2oai/h2o-2,111t8e/h2o-2,eg-zhang/h2o-2,elkingtonmcb/h2o-2,eg-zhang/h2o-2,elkingtonmcb/h2o-2,eg-zhang/h2o-2,calvingit21/h2o-2,vbelakov/h2o,rowhit/h2o-2,h2oai/h2o-2,rowhit/h2o-2,eg-zhang/h2o-2,elkingtonmcb/h2o-2,elkingtonmcb/h2o-2,rowhit/h2o-2,eg-zhang/h2o-2,calvingit21/h2o-2,eg-zhang/h2o-2,h2oai/h2o,h2oai/h2o,100star/h2o,h2oai/h2o,vbelakov/h2o,h2oai/h2o-2,h2oai/h2o,111t8e/h2o-2,vbelakov/h2o,rowhit/h2o-2,elkingtonmcb/h2o-2,vbelakov/h2o,vbelakov/h2o,h2oai/h2o-2,h2oai/h2o-2,calvingit21/h2o-2,elkingtonmcb/h2o-2,111t8e/h2o-2,rowhit/h2o-2,h2oai/h2o-2,vbelakov/h2o,111t8e/h2o-2,vbelakov/h2o,calvingit21/h2o-2,calvingit21/h2o-2,h2oai/h2o,rowhit/h2o-2,111t8e/h2o-2,rowhit/h2o-2,100star/h2o,rowhit/h2o-2,h2oai/h2o,elkingtonmcb/h2o-2,h2oai/h2o-2,elkingtonmcb/h2o-2,h2oai/h2o,vbelakov/h2o,rowhit/h2o-2