prepdata.m

新的神经网络算法源程序

function [x,y,xcent,xhalf,ycent,yhalf] = prepdata(x,y)
%Prepdata: Data pre-processing
%
%	[x,y,xcent,xhalf,ycent,yhalf] = prepdata(x,y)

%	By Qinghua Zhang. April 10, 1992.

if nargin ~= 2
  error('Number of input arguments error.');
end

[xl, xc] = size(x);
[yl, yc] = size(y);

if xc ~= yc
  error('x and y must have the same number of columns.');
end

if yl ~= 1
  error('y must be a row vector.');
end

xmax = max(x')';
xmin = min(x')';

xcent = 0.5 * (xmax + xmin); % centter of x domain
xhalf = 0.5 * (xmax - xmin); % half larger of x domain

x = (x - (xcent * ones(1,xc))) ./ (xhalf * ones(1,xc));

ymax = max(y')';
ymin = min(y')';

ycent = 0.5 * (ymax + ymin); % centter of y domain
yhalf = 0.5 * (ymax - ymin); % half larger of y domain

y = (y - ycent) ./ (yhalf * ones(1,yc));