%变量初始化，a为函数差值的上下限及插值点数，b为函数f(x)=1/(1+25*x*x)a=[-1:1];b=[1./(1+25.*a.*a)];[m,n]=size(a)x=[-1:0.1:1];y=0;%实现拉格朗日差值过程for k=1:n z=1; for j=1:n if j~=k z=z.*(x-a(j))./(a(j)-a(k)); end end y=y+b(k).*z;endplot(x,y)
