How can I get MATLAB to select a random variable from a set of variables?

I'm trying to write a program that generates a random combination based on variables. For example, the first set has variables A through D and a second set has variables E through H. I want to generate combinations from both sets like AE, DH, CF, etc.

Answer 1

[Image Analyst]

I don't know what AE etc. means. Do you mean to concatenate them, like [A, E]? If so try this:

% Assign 4 variables.
a=1;
b=2;
c=3;
d=4;
r1 = randi(4)
% Select one of them at random.
switch r1
  case 1
    out1 = a
  case 2
    out1 = b
  case 3
    out1 = c
  otherwise
    out1 = d
end
% Assign 4 variables.
e=11;
f=12;
g=13;
h=14;
% Select one of them at random.
r2 = randi(4)
switch r2
  case 1
    out2 = e
  case 2
    out2 = f
  case 3
    out2 = g
  otherwise
    out2 = h;
end
% Now make the concatenation
out = [out1, out2]

[Martin Cabal]

Thank you! This is exactly what I needed!

Answer 2

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/304602-out-of-memory-error-using-ndgrid

The functions I show there are for 6 sets, but otherwise the code is generalized -- notice there that the first thing I do is toss the values to select from into a cell array, so you can follow on from after that step if your values are already in a cell array.