how can I edit a matrix and rename it at the same time?

I start with a random matrix and edit the 8th column to new numbers and then rename it. what I thought was this:

my_matrix = rand(4,9)
my_matrix(:,8) = [2;4;6;1]
edited_matrix = my_matrix

however, I want to rename and edit the matrix in one go so at the end of the script, I have two matrices...

Almost like this (but this doesnt work)

my_matrix = rand(4,9)
edited_matrix = [my_matrix(:,8) = [2;4;6;1]]

so at the end I have two variables, my_matrix and edited_matrix that are different and can be reffered to separately

Answer 1

[Guillaume]

Sorry, you're better off doing it in two lines. You want to copy the matrix into the new variable before changing it so:

edited_matrix = my_matrix;
edited_matrix(:, 8) = [2 4 6 1];

If you really want to do it in just one line, you could do:

edited_matrix = [my_matrix(:, 1:7), [2;4;6;1], my_matrix(:, 9:end)];

but it's actually less readable and probably slower to execute.

Answer 2

[Thorsten]

You can do it like this:

my_matrix = rand(4,9);
edited_matrix = my_matrix;
edited_matrix(:,8) = [2;4;6;1];

[Matthew Perry]

thanks for that, really helpful!