I have a question about gathering same numbers together in a matrix

Hello,

I have a matrix with 104x3 format.

In the third column I have values from 1 to 4. and the first 2 column I have different values. Let me give a quick and basic example:

15 20 1

45 30 1

12 10 1

48 78 3

18 16 4

20 56 3

13 14 1

17 85 3

14 55 2

33 6 4

45 7 4

and so on.

What I would like to do is to see the matrix in a form like, all the 1 values that are in the third column are one under the other, after that I want to see two's and then 3's and 4's like that:

x x 1

x x 1

x x 1

x x 2

x x 2

x x 3

x x 3

x x 3

x x 4

Is there a quick way to make this happen?

Thank you

Answer 1

[the cyclist]

If M is your matrix, then

M_sorted = sortrows(M,3)

will output M sorted by the 3rd column, maintaining the order of the other two columns. See the documentation for sortrows for details.