How to flip only some rows inside a matrix?

Hi, I have a matrix xx which is a 6x20 matrix, and I want to flip only the even rows. Im trying this but is doesn't work:

f=size(xx);

f=f(1);

f=0:1:f;

f=f';

for s=f+2

        xx(f,:)=fliplr(xx(f,:));

end

I will appreciate any advice. Martha

Answer 1

[Azzi Abdelmalek]

A(2:2:end,:)=fliplr(A(2:2:end,:))

Answer 2

[the cyclist]

No need for a loop. Just do this:

xx(2:2:end,:) = fliplr(xx(2:2:end,:));

Answer 3

[VAISHNAVI GATTU]

hello, how to rotate certain elements in different rows in a matrix? for example a=[1 2 3 8; 4 5 6 4; 7 8 9 3] suppose i want all elements in second and third column to be rotated row wise. output should be a=[1 5 6 8; 4 8 9 4; 7 2 3 3]

[Martha]

a(:,2:3)=circshift(a(:,2:3),-1)