How do I add an integer to every or any nth row

Fairly new to MATLAB so I am just playing around to familiarize myself with it.

Lets say I have a 4x4 matrix, "A", how would I add for exaple 2 to every element in every other row (in this instance odd rows)? How would this differ if I wanted it for every nth row?

A = [1 1 0 0; 1 1 0 0; 0 0 0 0; 0 0 0 0]

desired output:

A = [3 3 2 2; 1 1 0 0; 2 2 2 2; 0 0 0 0]

Answer 1

[James Tursa]

A(k,:) is the k'th row of A

A(:,k) is the k'th column of A

A([k m p],:) is the sub-matrix formed from the k'th, m'th, and p'th rows of A

A(:,[k m p]) is the sub-matrix formed from the k'th, m'th, and p'th columns of A

A(1:5:end,:) is the sub-matrix formed from every 5'th row of A

A(:,1:5:end) is the sub-matrix formed from every 5'th column of A

etc.

To add a number to such sub-matrices, simply put them in an assignment

A(whatever) = A(whatever) + number;

The "whatever" is the indexing you want to pick off rows or columns etc.

[hbcukid]

Thank you so much, it worked! Still a little confused on the

A([k m p],:) is the sub-matrix formed from the k'th, m'th, and p'th rows of A
A(:,[k m p]) is the sub-matrix formed from the k'th, m'th, and p'th columns of A

part but will try to do additional reading