enumerate all possible combinations of an input space

for example I have 3 categorical variable, X1 can be 'A,B,or C', X2 can be 'A or D', X3 can be 'E or F', so there can be 3X2X2 different possible combinations:

AAE,AAF, ADE,ADF,BAE,BAF,BDE,BDF,CAE,CAF,CDE,CDF.

which function sould I use to create such a complete list?

Answer 1

[Walter Roberson]

X1 = categorical({'A', 'B', 'C'})

X1 = 1×3 categorical array
     A      B      C 

X2 = categorical({'A', 'D'})

X2 = 1×2 categorical array
     A      D 

X3 = categorical({'E', 'F'})

X3 = 1×2 categorical array
     E      F 

[X1g, X2g, X3g] = ndgrid(X1, X2, X3);
output = [X1g(:), X2g(:), X3g(:)]

output = 12×3 categorical array
     A      A      E 
     B      A      E 
     C      A      E 
     A      D      E 
     B      D      E 
     C      D      E 
     A      A      F 
     B      A      F 
     C      A      F 
     A      D      F 
     B      D      F 
     C      D      F