fonction.m

关于遗传算法的matlab程序

function  [xz,y,z] = fonction(arg1,arg2);
%PEAKS  A sample function of two variables.
%   PEAKS is a function of two variables, obtained by translating and
%   scaling Gaussian distributions, which is useful for demonstrating
%   MESH, SURF, PCOLOR, CONTOUR, etc.
%   There are several variants of the calling sequence:
%
%       Z = PEAKS;
%       Z = PEAKS(N);
%       Z = PEAKS(V);
%       Z = PEAKS(X,Y);
%
%       PEAKS;
%       PEAKS(N);
%       PEAKS(V);
%       PEAKS(X,Y);
%
%       [X,Y,Z] = PEAKS;
%       [X,Y,Z] = PEAKS(N);
%       [X,Y,Z] = PEAKS(V);
%
%   The first variant produces a 49-by-49 matrix.
%   The second variant produces an N-by-N matrix.
%   The third variant produces an N-by-N matrix where N = length(V).
%   The fourth variant evaluates the function at the given X and Y,
%   which must be the same size.  The resulting Z is also that size.
%
%   The next four variants, with no output arguments, do a SURF
%   plot of the result.
%
%   The last three variants also produce two matrices, X and Y, for
%   use in commands such as PCOLOR(X,Y,Z) or SURF(X,Y,Z,DEL2(Z)).
%
%   If not given as input, the underlying matrices X and Y are
%       [X,Y] = MESHGRID(V,V) 
%   where V is a given vector, or V is a vector of length N with
%   elements equally spaced from -3 to 3.  If no input argument is
%   given, the default N is 49.

%   CBM, 2-1-92, 8-11-92, 4-30-94.
%   Copyright 1984-2002 The MathWorks, Inc. 
%   $Revision: 5.10 $  $Date: 2002/04/08 20:04:50 $

if nargin == 0
    dx = 1/8;
    [x,y] = meshgrid(-3:dx:3);
elseif nargin == 1
    if length(arg1) == 1
        [x,y] = meshgrid(-3:6/(arg1-1):3);
    else
        [x,y] = meshgrid(arg1,arg1);     
    end
else
    x = arg1; y = arg2;
end

z =  exp(-(x-0.5).^2)+exp(-(y-0.7).^2)+(1/25)*exp(-(x+0.2).^2)+(1/25)*exp(-(x-0.2).^2)+(1/25)*exp(-(y+1).^2)+(1/25)*exp(-(y-1).^2);

if nargout > 1
    xz = x;
elseif nargout == 1
    xz = z;
else
    % Self demonstration
  
    surf(x,y,z)
    axis([min(min(x)) max(max(x)) min(min(y)) max(max(y)) ...
          min(min(z)) max(max(z))])
    xlabel('x'), ylabel('y'), title('L a fonction