work02.m

实现10次lagrange插值L（x）和三次样条插值

clear all;
m=1000;n = 11;
x = -1:2/(m-1):1;
y = 1./(1+9*x.^2);
x0 = -1:2/(n-1):1;
y0 = 1./(1+9*x0.^2);
y1 = lagr1(x0,y0,x);
y2 = interp1(x0,y0,x,'spline');
subplot(3,1,1);
plot(x,y);ylabel('y=f(x)');
subplot(3,1,2);
plot(x,y1);ylabel('y=L10(x)');
subplot(3,1,3);
plot(x,y2);ylabel('y=S(x)');