Matrix with full combinations of vectors'/matrices' elements

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Luca Freilino on 13 Apr 2019
Edited: Stephen Cobeldick on 13 Apr 2019
Hi everyone. I have a problem. I have 2 vectors and 2 matrices, that come from the nchoosek function. I'd like to know if there is a way to find a final matrix with all the possible combinations of their elements. E.g. A = [1 2 3] B = [4 5; 6 7] C = [8 9; 10 11] D = [12 13]. The final matrix should be: [1 4 5 8 9 12; 1 4 5 8 9 13; 1 4 5 10 11 12; ............ 2 6 7 10 11 12; 2 6 7 10 11 13; ............ Etc]
I have already tried with some for cycle (and it works), but I would like to find a faster and better solution. Thank you in advance, Luca

Stephen Cobeldick on 13 Apr 2019
Edited: Stephen Cobeldick on 13 Apr 2019
>> A = [1;2;3]; % Column vector!
>> B = [4,5;6,7];
>> C = [8,9;10,11];
>> D = [12;13]; % Column vector!
>> An = size(A,1);
>> Bn = size(B,1);
>> Cn = size(C,1);
>> Dn = size(D,1);
>> [Dx,Cx,Bx,Ax] = ndgrid(1:Dn,1:Cn,1:Bn,1:An);
>> Z = [A(Ax(:),:),B(Bx(:),:),C(Cx(:),:),D(Dx(:),:)];
Z =
1 4 5 8 9 12
1 4 5 8 9 13
1 4 5 10 11 12
1 4 5 10 11 13
1 6 7 8 9 12
1 6 7 8 9 13
... lots of rows here
3 4 5 10 11 12
3 4 5 10 11 13
3 6 7 8 9 12
3 6 7 8 9 13
3 6 7 10 11 12
3 6 7 10 11 13