Help plotting interpolation ploynomial.

1 次查看(过去 30 天)
Yuval
Yuval 2013-11-1
评论: Matt J 2021-3-21
Hi, I was asked to plot psi_n(x) = (x-x_0)(x-x_1)...(x-x_n) for n = 3,7,10,17 evenly distributed nodes in [-5,5] with resolution 0.01. Below is my code:
x=-5:0.01:5;
n=[3 7 10 17];
for j=1:4
node=-5;
psi=1;
while (node <= 5)
psi=psi.*(x-node);
node=node + 10/n(j);
end
subplot(2,2,j);
plot(psi)
hold on
end
Which doesn't quite yield the desired output. Or does it? In any case, it doesn't seem to match what I am getting via using Wolfram. My question is why and, of course, how may I correct it? I'd sincerely appreciate your assistance. Thanks in advance!

回答(1 个)

Matt J
Matt J 2013-11-1
编辑:Matt J 2013-11-1
node=linspace(-5,5,n);
p=poly(node);
f=@(z) polyval(p,z);
x=-5:0.01:5;
plot(x,f(x));
  4 个评论
Victor McNstein
Victor McNstein 2021-3-20
Hello Matt. How does on combine your code with Yuval's initial work, for better results?
Matt J
Matt J 2021-3-21
I do not see what Yuval thought was incomplete about my code. I think my code already fulfills the entire task.

请先登录,再进行评论。

类别

Help CenterFile Exchange 中查找有关 Interpolation 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by