Calling a function

I have a code that converts a matrix into its upper form and lower form counterparts.

I want to use this M file script in another M file script, where I take the L and U matrices for this new script that will take these L and U and use them to find the inverse of the matrix.

The problem is when I call the function, I can't use anything from the function I am calling.

Ie: I have the code:

function [L, U] = LU_decomp(A)

A=input('Enter the square matrix to be factorized     ');
[m,n]=size(A);
if m~=n 
    disp('Matrix must be square')

end
U=zeros(m);
L=zeros(m);
for j=1:m
    L(j,j)=1;
end
for j=1:m
    U(1,j)=A(1,j);
end
for i=2:m
    for j=1:m
        for k=1:i-1
            s1=0;
            if k==1
                s1=0;
            else
            for p=1:k-1
                s1=s1+L(i,p)*U(p,k);
            end
            end
            L(i,k)=(A(i,k)-s1)/U(k,k);
           end
         for k=i:m
             s2=0;
           for p=1:i-1
               s2=s2+L(i,p)*U(p,k);
           end
           U(i,k)=A(i,k)-s2;
         end
    end
end
disp('The matrix to be decomposed is')
A
disp('The Lower Triangular Matrix is')
L
disp('The Upper Triangular Matrix is')
U

So when a matrix is entered, it is split into its L and U form.

Now I have this other script:

function A =inverse(A)

LU_decomp(A)

L
U

I haven't completed the code for the inverse yet, but f I try the above script, entering in the matrix I want to use, LU_decomp calculates L and U forms, but then if I am trying using L and U in the body of my inverse script, L and U will be unrecognized. Why is this?Am I not calling the function correctly? (I'd rather split this up into two separate m-files than keep it in one.)

Answer 1

[Walter Roberson]

Call

[L, U] = LU_decomp(A);