Output of function not variable I assign

When I run this function I want that vector to be called u so I can use it in another script file. Instead it calls it "ans" which I can't use. What is going on? Here is the function, just run it for n=4.

function [u]=finitevolume_KG(n)

 %n is the number of volumes
 delta_x = 1/n;

 A=zeros(n-1);
 A(1,1)=1;
 A(1,2)=-1;
 for i=2:n-2
     A(i,i-1)=-1;
     A(i,i)=2;
     A(i,i+1)=-1;
 end
 for i=n-1
     A(i,i-1)=-1;
     A(i,i)=2;
 end

 f=ones(n-1,1);
 f_x=((delta_x)^2)*f;

 u = (A)\(f_x);

Answer 1

[per isakson]

Try the call

    u = finitevolume_KG( 4 )

and make it a habit to end your functions with the keyword "end".

[Jan]

I still omit the trailing "end" to support the small part of Matlab 6.5 users.

[per isakson]

Yes, but "end" kind of indicates the end of the workspace of the function.

Answer 2

[Jan]

Some simplifications:

function u = finitevolume_KG(n)

%n is the number of volumes
delta_x = 1/n;

A = zeros(n-1, n-1);
A(1,1) = 1;
A(1,2) = -1;
A(2:n-2, 1:n-3) = -1;
A(2:n-2, 2:n-2) = 2;
A(2:n-2, 3:n-1) = -1;

A(n-1, n-2) = -1;
A(n-1, n-1) = 2;

u = A \ (delta_x ^ 2 * ones(n-1, 1));