%曲線擬和：最小二乘法

function [xishu, e]=duoxiangshinihe(x0, y0,m)

n=length(x0);
for i=1:m+1
    for j=1:m+1
        a(i,j)=sum(x0.^(i+j-2));        
    end
    b(i)=sum(x0.^(i-1).*y0);
end
b=b';
xishu=inv(a)*b;
xishu=xishu';
y=0;
for i=1:m+1
    y=y+xishu(i)*x0.^(i-1);
end

e=sum((y-y0).^2);