How to calculate the angle between two lines from the same origin?
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Please I need help on this, I have extracted severla minutia points from this fingerprint image and I have been able to calculate the angle of each minutia according to the ridge direction, which i have dipslayed in green small arrows, and i want to take one of the minutia as a reference point and calculate the distance and angle each other minutia forms with the reference minutia, that is the angles in orange color, please help me on this. thanks
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Accepted Answer
KSSV
on 9 Jun 2020
O = [0. 0.] ; % origin
% Two points
A = rand(1,2) ;
B = rand(1,2) ;
u = O-A ;
v = O-B ;
CosTheta = (dot(u,v) / (norm(u)*norm(v)));
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More Answers (1)
David Hill
on 9 Jun 2020
Seems like just a math problem. If you have two vectors A and B, then angle between them is:
angle = acos(dot(A,B)/norm(A)/norm(B));
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David Hill
on 9 Jun 2020
You need four pixel points, to generate the three vectors from the origin. It does not matter what the magnitudes are since they get divided out to compute the angle.
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