double integral implementation in matlab

I am in trouble to implement the following double integral. there is a summation inside the integral which make things a bit complicated. The matlab code I did is as follows and always has error like "Matrix dimensions must agree." , any hint to implement it? thanks

n=3;
nn=1:n;
aa=gamma([1:n])
thre=3;
lapha=4;
r=3;
fun1= @(theta, x) (1-sum( lambda *pi *( (x-r).^2+r^2-(x-r).*r.*cos(theta)).^(nn-1)./aa).*exp(-1*lambda *pi*((x-r).^2+r^2-(x-r).*r.*cos(theta)))).*lambda/n*(1-1/2^n).*thre.*r.^alpha.*(x-r).^(1-alpha) ;
answer=integral2( fun1, 0, 2*pi, 0, inf )

Answer 1

[Torsten]

Note that x and theta are arrays, not scalars. This is in conflict with your summation.

Supply the function to be integrated in a separate .m-file where you perform the summation in a while-loop.

Best wishes

Torsten.

Answer 2

[khadija sofi]

Hello,

I have the same shape of integral, and i still have some problems, did you manage to calculate the integral above ? could you please tell me more of how to do it ?

Thank you in advance