all possible combinations of three vectors

I am trying to find all possible combinations of three vectors (A,B,C). For this, I tried using combvec. However, the result gets me a 1281x1 double, while i expected a matrix of 546*33*649 possibilities.

What i would like to get is:

A: 1,5,6,9,12

B: 1,2,3,4,5,6

C: 3,18,27,69,72

Ans:

1,1,3

1,1,18

1,1,27

etc.

So how do i do this?

Answer 1

[Guillaume]

One possible way, which doesn't require any toolbox:

 [ca, cb, cc] = ndgrid(A, B, C);
 combs = [ca(:), cb(:), cc(:)]

[Rogier Busscher]

It seems to be working, thank you dearly!

[Devsmit Ranparia]

@guillaume is it possible use ndgrid when I don't know explicilty the number of output arguements. Based on some number 'n' my code must be able to keep output arguements as [x1,x2,...,xn] = ndgrid(X).

Thanks in advance!

[Bruno Luong]

x=cell(1,n)
[x{:}] = ndgrid(X)

[Abdelmajid Ben yahya]

Hi,

I have an additional question, if i may.

Is it possible to get all combinations that fulfil a certain constraint? Let's say that within the combination A+B+C<=4.

Thank you.

[Bruno Luong]

Just filter out those are not meet the constraints, or you can use this FEX to get directly the combination

allVL1(3,4,'<=')

ans =

     0     0     0
     0     0     1
     0     1     0
     1     0     0
     0     0     2
     0     1     1
     0     2     0
     1     0     1
     1     1     0
     2     0     0
     0     0     3
     0     1     2
     0     2     1
     0     3     0
     1     0     2
     1     1     1
     1     2     0
     2     0     1
     2     1     0
     3     0     0
     0     0     4
     0     1     3
     0     2     2
     0     3     1
     0     4     0
     1     0     3
     1     1     2
     1     2     1
     1     3     0
     2     0     2
     2     1     1
     2     2     0
     3     0     1
     3     1     0
     4     0     0

Answer 2

[Azzi Abdelmalek]

A=[1,5,6,9,12]
B= [1,2,3,4,5,6]
C= [3,18,27,69,72]
[ii,jj,kk]=meshgrid(A,B,C);
ii=permute(ii,[1 3 2]);
jj=permute(jj,[2 1 3])
kk=permute(kk,[3  2 1])
out=[ii(:) jj(:) kk(:)];