svkernel.m

用工具箱做的

function k = svkernel(ker,u,v)
            
%  Author: Steve Gunn ([e-mail])

  if (nargin < 1) % check correct number of arguments
     help svkernel
  else
     
    global p1 p2;

    % could check for correct number of args in here
    % but will slow things down further
    switch lower(ker)
      case 'linear'
        k = u*v';
      case 'poly'
        k = (u*v' + 1)^p1;
      case 'rbf'
        k = exp(-(u-v)*(u-v)'/(2*p1^2));
      case 'erbf'
        k = exp(-sqrt((u-v)*(u-v)')/(2*p1^2));
      case 'waveff'
        z= cos(1.75*(u-v)/0.6)*exp(-(abs(u-v))^2/(2*0.6^2));
        k = prod(z);

      otherwise
        k = u*v';
    end

  end