HOW TO REPLACE SPECIFIC ELEMENTS IN A MATRICE?

Consider a 5x5 matrix A

How to replace the numbers on the locations (2:3,3) and (4,3:5) with zeros.

Help needed !!

Answer 1

[Jan]

A = rand(5, 5);

A(2:3, 3) = 0;
A(4, 3:5) = 0;

Is this a homework question? If so: what a pity that you did not try it by your own. You see, that the translation from English to Matlab is not hard in this case.

Can you find an alternative using logical indexing, which inserts the zeros in one command?

[Muhammad Safwan Khan]

THANKS FOR HELPING

I'm Beginner & it is my first experience of practicing matlab.I didn't know much about it but hope gradually i will ace it..

[Jan]

Do you know Matlab's onramp tutorial already? https://www.mathworks.com/learn/tutorials/matlab-onramp.html

The "Getting Started" chapters of the documentations are useful also.

With "logical indexing" (index using a logical mask):

A([0,0,0,0,0; ...
   0,0,1,0,0; ...
   0,0,1,0,0; ...
   0,0,1,1,1; ...
   0,0,0,0,0] == 1) = 0

With "linear indexing":

A([12, 13, 14, 19, 24]) = 0;

Here the elements are treated as A is a 1D vector.