lagrag.txt

包括牛顿法

function [c,l]=lagran(x,y) 
w=length(x);
n=w-1;
l=zeros(w,w);
for k=1:n+1
v=1;
for j=1:n+1
if k~=j
v=conv(v,poly(x(j)))/(x(k)-x(j));
end
end
l(k,:)=v;
end
c=y*l;