how to find cosine angle known the end points of 2 linesegments
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There are 2 line segments, known their end points, how can i find angle between them
Accepted Answer
Guillaume
on 29 Apr 2015
The arguments you pass to dot and norm must be vectors not scalars
v1 = [1 1]
v2 = [0 3]
D = [v1;v2]; %possibly you have something like this
costheta = dot(D(1, :), D(2, :)) / (norm(D(1, :)) * norm(D(2, :)));
thetaindegrees = acosd(costheta)
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More Answers (1)
Roger Stafford
on 29 Apr 2015
Edited: Roger Stafford
on 29 Apr 2015
Using 'atan2' or 'atan2d' and cross product is more accurate for angles that are near zero or near pi (180 degrees.)
a = atan2(norm(cross(D1,D2)),dot(D1,D2)); % Angle in radians
or
a = atan2d(norm(cross(D1,D2)),dot(D1,D2)); % Angle in degrees
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