How to add a new column into the already existing matrix after satisfying certain condition?

I would like to compare a condition of each newly inserted column with already existing column in the matrix. If the condition doesn't meets,then the new column should be added into the matrix. otherwise the old column should be altered into new column.

Answer 1

[Eng. Fredius Magige]

We didnt catch, be specific, assume you have C=[4 1 2; 4 8 3]; % then assume you want to add on top of it, just do C(:,4)=[8; 10]; % you can manipulation your task the same way, you get C=[4 1 2 8; 4 8 3 10]