1 ## Copyright (C) 2006 Michel D. Schmid <michaelschmid@users.sourceforge.net>
4 ## This program is free software; you can redistribute it and/or modify it
5 ## under the terms of the GNU General Public License as published by
6 ## the Free Software Foundation; either version 2, or (at your option)
9 ## This program is distributed in the hope that it will be useful, but
10 ## WITHOUT ANY WARRANTY; without even the implied warranty of
11 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 ## General Public License for more details.
14 ## You should have received a copy of the GNU General Public License
15 ## along with this program; see the file COPYING. If not, see
16 ## <http://www.gnu.org/licenses/>.
19 ## @deftypefn {Function File} {}@var{a} = tansig (@var{n})
20 ## @code{tansig} is a non-linear transfer function used to train
22 ## This function can be used in newff(...) to create a new feed forward
23 ## multi-layer neural network.
27 ## @seealso{purelin, logsig}
29 ## Author: Michel D. Schmid
32 function a = tansig(n)
34 ## see MATLAB(TM) online help
35 a = 2 ./ (1 + exp(-2*n)) - 1;
36 ## attention with critical values ==> infinite values