All combinations

% 'alphabet' is an array of L element.n is a positive integer representing
% the number of places in which the elements of 'alphabet' are arranged.
% m=all_comb(alphabet,n) returns an (L^n X n) matrix of all possible
% n-digit combinations of the elements of a given L-element alphabet.
% This function is very useful in finding all possible n-digit numbers
% that may be constructed from a set of digits; and when char(m) is used,
% all possible n-letter words that may constructed from a group of letters
% is found by this function.
% NOTE THAT the transposition operation used in this function in line 35
% will change complex-valued entries to their complex conjugate.
%
% By: Abdulrahman Ikram Siddiq
% Kirkuk - IRAQ
% Thursday Oct.27th 2011 11:15 PM