Getting Started

Deleting Rows and Columns

You can delete rows and columns from a matrix using just a pair of square brackets. Start with

X = A;

Then, to delete the second column of X, use

X(:,2) = []

This changes X to

X =
    16     2    13
     5    11     8 
     9     7    12
     4    14     1

If you delete a single element from a matrix, the result isn't a matrix anymore. So, expressions like

X(1,2) = []

result in an error. However, using a single subscript deletes a single element, or sequence of elements, and reshapes the remaining elements into a row vector. So

X(2:2:10) = []

results in

X =
    16     9     2     7    13    12     1

Concatenation

More About Matrices and Arrays