How to eliminate certain columns from a matrix

If I need to remove any column how do I do it?

For example:

s is a mxn matrix.I need to remove the odd columns i,e, the 1st,3rd.. columns.

Answer 1

[KSSV]

Let A be matrix

A(:,1:2:end) = []    % remove odd columns
A(:,3) = []       % remove third column
idx = [1 2 5 7] ;
A(:,idx) = []  % remove columns specified in idx 

Answer 2

[Manvi Goel]

Let the matrix be a.

You can remove the odd columns of a matrix by :

a(:,1:2:end) = [] 
% 1:2:end runs a loop from 1 till the numbe rof columns, increments the index by 2 every time and 
% empties the column with that index.

Or use the following command to remove and column with index 'i'

a(:, i) = []