All Possible Combinations of 2 vectors

Hi everybody,

I have a simple question.

I'm trying to generate rapidly a matrix with all combinations of 2 vectors.

I'm working on the classification of bridge damages. The damage is expressed with a qualitative number ranging from 1 to 5 (the first vector) CR=1:5, the other vector is the position of damage on the bridge ranging also it from 1 to 5 (a fifth of the length per time).

I just would like to have the matrix that containts as the number of rows the combinations of CR, and as the number of columns the ith position.

I would like to have a scheme to follow.

It should look like:

A=[1 1 1 1 1; 2 1 1 1 1; ..; 3 4 5 1 1; ...]

excluding the repetitions.

I tried different commands but i'm not finding the solution!

Thanks in advance!

G

Answer 1

[Stephen23]

>> [A,B,C,D,E] = ndgrid(1:5);
>> M = [A(:),B(:),C(:),D(:),E(:)];
M =
   1   1   1   1   1
   2   1   1   1   1
   3   1   1   1   1
   4   1   1   1   1
   5   1   1   1   1
   1   2   1   1   1
   2   2   1   1   1
   3   2   1   1   1
... lots of lines here
   2   4   5   5   5
   3   4   5   5   5
   4   4   5   5   5
   5   4   5   5   5
   1   5   5   5   5
   2   5   5   5   5
   3   5   5   5   5
   4   5   5   5   5
   5   5   5   5   5

Answer 2

[KSSV]

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