Removing Rows or Columns from a Matrix

The easiest way to remove a row or column of a matrix is setting that row or column equal to a pair of empty square brackets []. For example, create a 4-by-4 matrix and remove the second row.

A = magic(4)
A = 4×4

    16     2     3    13
     5    11    10     8
     9     7     6    12
     4    14    15     1

A(2,:) = []
A = 3×4

    16     2     3    13
     9     7     6    12
     4    14    15     1

Now remove the third column.

A(:,3) = []
A = 3×3

    16     2    13
     9     7    12
     4    14     1

You can extend this approach to any array. For example, create a random 3-by-3-by-3 array and remove all of the elements in the first matrix of the third dimension.

B = rand(3,3,3);
B(:,:,1) = [];

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