How can this code run through all possible combinations of numbers in two separate arrays?

Here is the problem I am having (on a small scale): what I need to do is take combinations of values from two separate matrices and treat them as inputs in an equation. I would like to input all possible combinations of the two parameters. For example:

A = [1 2 3]

B = [4 5 6]

y = (1 element of A) + (1 element of B)

Possible combinations to be used as inputs in an equation:

1 and 4

1 and 5

1 and 6

2 and 4

2 and 5

etc.

What is the best way to go about coding this?

Answer 1

[Image Analyst]

You can use meshgrid:

A = [1 2 3]
B = [4 5 6]
[AA, BB] = meshgrid(A, B)
% Convert to column vectors
AA = AA(:);
BB = BB(:);
for k = 1 : length(AA)
  fprintf('A = %d, B = %d\n', AA(k), BB(k));
end

[Matthew]

Image Analyst, you deserve a cookie.

[Image Analyst]

Regarding your comment to Roger, to get the sums of all combinations:

theSums = AA + BB;

theSums is a vector of all possible sums.

Answer 2

[Roger Stafford]

Use for-loops:

   for iA = 1:length(A)
     a = A(iA);
     for iB = 1:length(B)
       b = B(ib);
       % Use a and b as inputs
     end
   end

[Matthew]

This doesn't quite solve the problem. This outputs the last value of each array (as a and b), but doesn't provide me with a way to place every possible input combination into the equation. So instead of receiving answers like

y = [1+4 , 1+5, ... , 3+6]

I only receive

y = [3+6]

[Roger Stafford]

I disagree, Matthew. Each possible combination of a pairing from A and B are used as inputs a and b in those for-loops. In your example, there would be nine different combinations that would occur as inputs.

Is there something about your using pairs as inputs that you are not telling us? Perhaps you should explain at greater lengths what you mean by " Possible combinations to be used as inputs in an equation. "