I am quite confused as to the desired output. Your code produces: 
oooooooooooooooooooo
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oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo
oooooooooooooooooooo

[download]
I don't understand what that means? There is a Math::Trig module that can deal with rectangular and spherical coordinates or 2 dimensional versions (x,y and polar,magnitude and angle). Sorry that I'm being dense, but I don't understand the requirement yet.

Update: Just as a wild thought, maybe this is a graphical representation of a target grid? You are going to drop a bomb at a particular coordinate in this grid with a blast radius of X. All of the affected "o's" should turn into "x's". Is that analogy right?

In reply to Re: circular area in a coordinates grid (AoA) by Marshall
in thread circular area in a coordinates grid (AoA) by Discipulus

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