shawn bright wrote:
> hey there all,
> 
> ok, not really a ruby question, but did not know where to look.
> i have a circle on a graph paper.
> if i know the x and y of a point on the graph, if the center is at
> 0,0, and i know the radius,
> how can i find the angle that the point will be on the circumference?
> somewhere between 1-360.
> 
> would appreciate any tips, thanks
> ok, if it is really against the grain to post this question here,
> anyone have a recommendation of where to put it?
> thanks all
> 
> sk

irb(main):007:0> Math.atan2(-1.0, -1.0)*180/Math::PI % 360
=> 225.0
irb(main):008:0> Math.atan2(-1.0, 1.0)*180/Math::PI % 360
=> 315.0
irb(main):009:0> Math.atan2(1.0, 1.0)*180/Math::PI % 360
=> 45.0
irb(main):010:0> Math.atan2(1.0, -1.0)*180/Math::PI % 360
=> 135.0

HTH.

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407