How to obtain the mirror image of an array (MATLAB)?

UPDATE: In newer versions of MATLAB (R2013b and after) it is preferred to use the function flip instead of flipdim, which has the same calling syntax:

a = flip(a, 1);  % Reverses elements in each column
a = flip(a, 2);  % Reverses elements in each row

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Tomas has the right answer. To add just a little, you can also use the more general flipdim:

a = flipdim(a, 1);  % Flips the rows of a
a = flipdim(a, 2);  % Flips the columns of a

An additional little trick... if for whatever reason you have to flip BOTH dimensions of a 2-D array, you can either call flipdim twice:

a = flipdim(flipdim(a, 1), 2);

or call rot90:

a = rot90(a, 2);  % Rotates matrix by 180 degrees

Another simple solution is

b = a(end:-1:1);

You can use this on a particular dimension, too.

b = a(:,end:-1:1); % Flip the columns of a

you can use

rowreverse = fliplr(row) %  for a row vector    (or each row of a 2D array)
colreverse = flipud(col) % for a column vector (or each column of a 2D array)

genreverse = x(end:-1:1) % for the general case of a 1D vector (either row or column)

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