ddifference.m

这是我从一本基于MATLAB实现的数值分析算法的书中自带的光盘程序

%2-2 均差表
function f=ddifference(xi,fi)
xi=[0.1,0.2,0.4,0.7,1.0,1.2,1.3];
fi=[0.99750,0.99002,0.96040,0.88120,0.76520,0.67113,0.62009];
n=length(fi);
ddf=zeros(size(xi));
fprintf('xi=%12.8f\n',xi);
fprintf('fi=%12.8f\n',fi);
for k=n-1:-1:1
    p=n-k;
    fprintf('k=%12.8f\n',k);
    for j=1:k
        ddf(j)=(fi(j+1)-fi(j))/(xi(j+p)-xi(j));
        fi(j)=ddf(j);
        fprintf('ddf(j)=%12.8f\n',ddf(j));
   end 
end
return