How to make a function output a matrix

I am trying to make a function that takes in multiple variables and outputs a matrix of values. The inputs are supposed to plug into the equation V, and output a matrix. My problem is that this outputs a vector instead of a matrix. How do I make it output a matrix?

function T = prob3_5(x,y,N,L,W,T1,T2)
V=zeros(1,length(x));
for n=1:2:N
for i=1:length(x)
V(i)=V(i)+(2/pi)*(2/n)*sin(n*pi*x(i)/L).*sinh(n*pi*y(i)/L)/sinh(n*pi*W/L);
end
T=(T2-T1)*V+T1;
end

[John D'Errico]

You create a vector. How are we supposed to know what matrix you need to construct, when all we see is code that creates a vector?

[SALAH ALRABEEI]

% This is a Fourier series why do you want a matrix, it is just an array
% because you just summing up the solution at each point of x and y. 
% The output is vector because T is V and V is defined as a vector V=zeros(1,length(x));

[Petch Anuwutthinawin]

the answer should have the same number of columns as elements in X, and the same number of rows as elements in Y.

Answer 1

[SALAH ALRABEEI]

I think you need only one loop that accomulate the series. I am assuming x and y are sent to the function as vectors, then we creat grid out of them

     T = prob3_5(x,y,N,L,W,T1,T2)
[x,y]=meshgrid(x,y);
V=zeros(size(x));
for n=1:2:N
V=V+(2/pi)*(2/n)*sin(n*pi*x/L).*sinh(n*pi*y/L)./sinh(n*pi*W/L);
T=(T2-T1)*V+T1;
end