function [w,b] = nwtan(s,p,z)
%NWTAN Nguyen-Widrow random generator for TANSIG neurons.
%  
%  This function is obselete.
%  Use INITNW to initialize a network layer.

nntobsf('nwtan','Use INITNW to initialize a network layer.')

%  [W,B] = NWTAN(S,P)
%    S - Number of neurons in layer.
%    P - Rx2 matrix of input value ranges.
%  Returns:
%    W - new SxR weight matrix.
%    B - new Sx1 bias vector.
%  
%  IMPORTANT: Each ith row of P must contain expected
%    min and max values for the ith input.
%  
%  EXAMPLE: [w,b] = nwtan([-5 5; 0 1],4)
%  
%  See also NNRAND, TANSIG, NWLOG.

% Mark Beale, 1-31-92
% Revised 12-15-93, MB.
% Copyright 1992-2002 The MathWorks, Inc.
% $Revision: 1.12 $  $Date: 2002/04/14 21:15:21 $

if nargin < 2,error('Not enough arguments.'); end
if nargout < 2, error('Not enough output arguments.'); end

% BACKWARD COMPATIBILITY FOR NNT 1.0
% Convert NWTAN(S,R,P) -> NWTAN(S,P)
if nargin == 3
  p = z;
end
% Convert NWTAN(S,R) -> NWTAN(S,P)
if nargin == 2 & length(p) == 1
  p = ones(p,1) * [-1 1];
end

[r,q] = size(p);
pmin = min(p')';
pmax = max(p')';

magw = 0.7*s^(1/r);
w = magw*randnr(s,r);
b = magw*rands(s,1);

rng = pmax-pmin;
mid = 0.5*(pmin+pmax);
w = 2*w./(ones(s,1)*rng');
b = b - w*mid;