How I make circular grid without using meshgrid or rectangle?

I made circle grid by using meshgrid of X and Y.Then I took the circle formula from the rectangular grid by following this code:

>>[x,y]=meshgrid(-128:127,-128:127); %(replicates the grid vectors from -128 to 127 to produce a full grid. This gridis represented by the output coordinate arrays X and Y).

>>z=sqrt(x.^2+y.^2); % is the formula for having the circle (Matrix) >>c=(z<14); % to cutoff 14 value >>figure,imshow(c)

My question is :How I make circular grid directly instead of making square or rectangle grid and then making circular formula with cutoff???

I hope to find the solution from the members in this website

thank you

[Anonymous]

How would I change the color of this circle? Also, how would I add another circle like this?

Answer 1

[Jos (10584)]

I think your approach is very straightforward. Everything I can think of right that does not generate grid points being thrown away later involves looping twice.

Moreover, your variable C needs to be rectangular if it is used by imshow ...