create matrix with integral

Asked by Mohammed Hachemi

Mohammed Hachemi (view profile)

on 15 Sep 2019
Latest activity Answered by Mohammed Hachemi

Mohammed Hachemi (view profile)

on 15 Sep 2019
Accepted Answer by Walter Roberson

Walter Roberson (view profile)

Hello
I need your help , I am beginner in matlab and want to use matlab to calculate integral and create matrix with variable n and m.
x = [-1,1]
∫ (f(x,n)*f(x,m)dx
I want to creat matrix
f(x,1)*(f(x,1) f(x,1)*(f(x,2) .....
f(x,2)*(f(x,1) f(x,1)*(f(x,1)
.
.
I try this code but I need your help to create one
P = 5; exemple
fun(1) =@(x)(1-x)/2;
fun(2) =@(x)(1+x)/2;
fun(n) =@(x) sin(pi/2*(n-1).*(1+x)); if n >= 2;
for m = 1:P;
for n = 1:P;
L[n,m]=integral((fun(m).*fun(n)),-1,1,-1,1);
end
end

Tags

Answer by Walter Roberson

Walter Roberson (view profile)

on 15 Sep 2019

P = 5;
for m = 1:P;
for n = 1:P;
L(n,m) = integral( @(x) fun(x,n).*fun(x,n)), -1, 1);
end
end
function y = fun(x, n)
%warning: x will be a vector or array!
if n == 1
y = (1-x)/2;
elseif n == 2
y = (1+x)/2;
else
y = sin(pi/2*(n-1).*(1+x));
end