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i have arc A ,i know startangle,endangle,startPoint,Endpoint,centre,radius of arc and i have point B, i like to find point B lies or not in arc A , i need formula or algorithum for this

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You probably need to worry about numeric precision. These are clearly floating point numbers and B may not be exactly on the arc, even if it should be. – Ross Millikan May 1 '14 at 0:04

Assuming you're talking about an arc of a circle, the first question to ask is whether the point lies on the circle. This just means that the distance from the center of the circle to your point is equal to the radius. Then find out the angle between the radius to your point and, say, a horizontal line, and figure out whether the point is within the bounds of the arc.

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@ratty. In the second step using $\arctan(y/x)$ is not sufficient. You must use atan2: – Jyotirmoy Bhattacharya Oct 6 '10 at 12:29

Did you take a look here:

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This sort of answers (pointing to a URL) is better as a comment, IMO. – anon Oct 6 '10 at 12:55
@Muad: Right, i keep that in Mind from now on. – anonymous Oct 6 '10 at 12:58

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