Subtracting Two Matrices of different sizes

How do I do the following subtraction: let X = [302 64] where all values in X are either 0s or 1s

A= X - X'; 

A=[302 64] - [64 302];

How do I find subtract these?

[Walter Roberson]

What size are you expecting the result to be?

For any one entry in the result, say A(J,K), how should A(J,K) be computed?

[AR]

Walter, Was expecting [302 302]; additionally I'm subtracting [302 64] - [64 140] and would like this to equal [302 140]. Hope this is possible as I'm stuck with many errors in do loop. Thx, Allen

[Walter Roberson]

For any one entry in the result, say A(J,K), how should A(J,K) be computed?

Answer 1

[Walter Roberson]

T1 = X;        %the left side
T2 = X';       %whatever the right side is

if any(size(T1) < size(T2))
  T1(size(T2,1),size(T2,2)) = 0;         %zero pad
end
if any(size(T2) < size(T1))
  T2(size(T1,1),size(T1,2)) = 0;         %zero pad
end
A = T1 - T2;

Answer 2

[Renato Agurto]

Hi

do you mean something like this?

%A,B: inputs matrices
%C output matrix

N = max([size(A,1) size(B,1)]);
M = max([size(A,2) size(B,2)]);

An = zeros(N,M);
Bn = zeros(N,M);

An(1:size(A,1), 1:1:size(A,2)) = A;
Bn(1:size(B,1), 1:1:size(B,2)) = B;

C = An-Bn

[AR]

Renato, Thanks. This way worked too. Allen