clc; clear all ;
A = [10,10]; B = [5,60];
C1=[ 11.1902 78.9215
43.7123 84.8152
26.2182 55.0542
89.4285 18.3821
41.1215 32.8977
62.8533 101.3337
26.5649 25.2378
70.1982 92.5817
36.2971 63.8342
75.4079 109.6135] ;
ABC = zeros(size(C1,1),1) ;
for i = 1:size(C1,1)
C = C1(i,:) ;
x = [B(1) A(1) C(1)];
y = [B(2) A(2) C(2)];
x1 = x(1); y1 = y(1);
x2 = x(2); y2 = y(2);
x3 = x(3); y3 = y(3);
ang1 = atan2(abs(det([x1,x2,x3;y1,y2,y3;1,1,1])), ...
(x2-x1)*(x3-x1)+(y2-y1)*(y3-y1));
ABC(i) =180/pi*(ang1) ;% this is ABC angle
end
