Make a matrix of different combinations.

Hello, all,

If we need to make different combinations, like the first three entries among {0,1,2} and the fourth entry is from {0,1,...,1000} how to make this matrix? There should be 3^3*1001 rows for that matrix.

Answer 1

[Walter Roberson]

See the "odometer" construction I describe in http://www.mathworks.com/matlabcentral/answers/29662-generate-points-sorted-by-distance

[C Zeng]

Thanks, I think I find another way to do it, define a 3-dimensional matrix. Thanks.

Answer 2

[Andrei Bobrov]

one way

[k1,k2,k3,k4] = ndgrid(0:2,0:2,0:2,0:1000);
out = [k1(:),k2(:),k3(:),k4(:)];

or

cmb = fullfact([3 3 3 1001]); % 'fullfact' from 'Statistics Toolbox'
d = 0:1000;
out = d(cmb);