Accessing alternate rows and columns in the matrix.

A =

1 2 3 4

5 6 7 8

9 10 11 12

13 14 15 16

How can I access alternate rows and columns e.g. 1st & third row and 2nd & 4th column from the above matrix?

Answer 1

[Star Strider]

Try this —

A = [ 1     2       3         4
      5     6       7         8
      9    10     11      12
     13    14    15     16];

Rows = A(1:2:end,:)

Rows = 2×4

1 2 3 4 9 10 11 12

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

Columns = 4×2

2 4 6 8 10 12 14 16

Both = A(1:2:end, 2:2:end)

Both = 2×2

2 4 10 12

EDIT — (26 Aug 2022 at 12:22)

Corrected typographical error.

.

[Permvir Singh]

I am still unable to access whole row and column.

[Star Strider]

It works here with the supplied ‘A’ matrix.

I am not certain what matrix you are working with if it is different from ‘A’ here. It could be a problem with the size of the matrix and the ability of whatever you are using to display all the numbers.