how can i extract circular data from matrix?

Hi,

I have axb double data, and I want to extract circular nxn data.

For example, as you can see in the jpg file I attached,

If there is data A (9x9 double),

I assign center as A(5,5) (orange), and diameter r=3,

then I want to extract 7x7 double data from A that I mark as green.

Thanks to all!

Answer 1

[madhan ravi]

Try reading the link below:

https://www.mathworks.com/matlabcentral/answers/409228-how-to-filter-out-annular-data-from-square-matrix