nvldtcknfun.m

数据挖掘的新方法－支持向量机书中算法例子

function L=NvlDtcKnFun(a);

Dim=size(a);
if Dim(1)<Dim(2),   % Conditioning the vector A as a column vector
    a=a';
end

fid=fopen('a.dat','r');
    s=fread(fid,1,'float');
    n=fread(fid,1,'float');
    x1=fread(fid,n,'float');
    x2=fread(fid,n,'float');
fclose(fid);


% Radius based Kernel Function K(x,y)=exp[-(x-y)*(x-y)'/s.^2], there x and y are 2-D vector, x=(x1,x2) which is to say; 
I=ones(1,n);
L=sum(sum(diag(a)*(    exp(   -((x1*I-(x1*I)').^2+(x2*I-(x2*I)').^2)/(s.^2)    )     )*diag(a))) + a'*a -1 ;