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Topic: calculating an angle between a point and a vector (kind of)
Replies: 2   Last Post: Jun 18, 2013 9:26 AM

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Narasimham

Posts: 350
Registered: 9/16/06
Re: calculating an angle between a point and a vector (kind of)
Posted: Jun 12, 2013 2:48 PM
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> Everythjing is in 2d.
>
> I have two points (p1 and p2). I know ther current
> x,y. One of those points (p1) has a bearing so on the
> grid it is more like a vector. I need to calculate
> the angle between the vector and the line p1p2.


A = x i + y j ; P = (x2 - x1) i + (y2 - y1) j

ArcCos(dot prod)/abs(A)/abs(P)

Narasimham



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