intersection of 3 cercles (intersect problem)

Question

Mohammed Ghedamsi 2015-2-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/178488-intersection-of-3-cercles-intersect-problem

编辑： Omar Elsayed 2017-5-26

 I am trying to find the intersection between 3 cercles.
I started with intersection between each 2 cercles with "circcirc" function 
then, to find the common point between [x1,y1] and [x2,y2] i used the intersect function but i got "Empty matrix: 1-by-0"

Can someone help me with this

%%Données pour configuation des transcepteurs
% Triangle equilateral inscrit dans un cercle de rayon R
R=50;
D=2*R;
a=D*sin(degtorad(60));
b=a; c=a;       
h=sqrt(3)/2*a;
B=h*2/3*(cos(degtorad(30))-sin(degtorad(30))*i);
A=-h*2/3*(cos(degtorad(30))+sin(degtorad(30))*i);
C=i*2*h/3;
figure;
plot(A,'o');
grid on
hold on
plot(B,'o');
plot(C,'o');
ang=0:0.01:2*pi; 
xp=R*cos(ang);
yp=R*sin(ang);
plot(xp,yp,'k');
axis('equal');
Tag=20+30i;
plot(Tag,'vk');
d1=sqrt((real(Tag)-real(A))^2+(imag(Tag)-imag(A))^2);
d2=sqrt((real(Tag)-real(B))^2+(imag(Tag)-imag(B))^2);
d3=sqrt((real(Tag)-real(C))^2+(imag(Tag)-imag(C))^2);
ang=0:0.01:2*pi; 
xp1=d1*cos(ang);
yp1=d1*sin(ang);
C1=real(A)+xp1+i*(imag(A)+yp1);
plot(C1,'b');
ang=0:0.01:2*pi; 
xp2=d2*cos(ang);
yp2=d2*sin(ang);
C2=real(B)+xp2+i*(imag(B)+yp2);
plot(C2,'g');
ang=0:0.01:2*pi; 
xp3=d3*cos(ang);
yp3=d3*sin(ang);
C3=real(C)+xp3+i*(imag(C)+yp3);
plot(C3,'r');
   [x1,y1]=circcirc(real(C),imag(C),d3,real(B),imag(B),d2);
   [x2,y2]=circcirc(real(C),imag(C),d3,real(A),imag(A),d1);
   TagExp= intersect(x1,x2)+i*intersect(y1,y2);