5
$\begingroup$

I have a huge matrix and would like to drop every other 4th row and every other 4th column in one shot. What is the element way to do that.

Regards,

$\endgroup$
9
$\begingroup$

Use Drop:

Drop[Array[a, {9, 9}], {4, -1, 4}, {4, -1, 4}] //TeXForm

$\left( \begin{array}{ccccccc} a(1,1) & a(1,2) & a(1,3) & a(1,5) & a(1,6) & a(1,7) & a(1,9) \\ a(2,1) & a(2,2) & a(2,3) & a(2,5) & a(2,6) & a(2,7) & a(2,9) \\ a(3,1) & a(3,2) & a(3,3) & a(3,5) & a(3,6) & a(3,7) & a(3,9) \\ a(5,1) & a(5,2) & a(5,3) & a(5,5) & a(5,6) & a(5,7) & a(5,9) \\ a(6,1) & a(6,2) & a(6,3) & a(6,5) & a(6,6) & a(6,7) & a(6,9) \\ a(7,1) & a(7,2) & a(7,3) & a(7,5) & a(7,6) & a(7,7) & a(7,9) \\ a(9,1) & a(9,2) & a(9,3) & a(9,5) & a(9,6) & a(9,7) & a(9,9) \\ \end{array} \right)$

$\endgroup$
  • $\begingroup$ Many thanks for your prompt answer. $\endgroup$ – qahtah Nov 21 '17 at 4:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.