How to create a function in Matlab or Mathcad for combination of all elements betweeen three sets -

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• generate possible combinations of elements of vectors (cartesian product) 3 answers

i have problem issue. so, have 3 sets 4 elements, e.g.:

[r11, r12, r13, r14] [r21, r22, r23, r24] [r31, r32, r33, r34] 

i need combination between these elements. each of elements in particular sets must in same place:

1. r11  r21 r31 2. r11  r21 r32        .        .        . n. r14  r24 r34 

how can in matlab or mathcad?

assuming sets s1, s2, s3 s1 [r11, r12, r13, r14]:

[a,b,c] = ndgrid(s3, s2, s1); [c(:), b(:), a(:)] 

for example input:

s1 = [1,2]; s2 = [10,20]; s3 = [100,200,300]; 

results in:

ans =       1    10   100      1    10   200      1    10   300      1    20   100      1    20   200      1    20   300      2    10   100      2    10   200      2    10   300      2    20   100      2    20   200      2    20   300