[交流] 【求助】急！！！！！高人请赐教

Originally posted by sobigstar11 at 2010-10-13 08:47:15:
我想请教您一下 两个圆已知圆心坐标和半径求交点坐标，MATLAB怎么实现，我用的SOLVE函数，可是结果得到的是复数值，不知道怎么回事，另外复数能在二维坐标系中作图吗

function IntersectPoints( Cx1, Cy1, r1, Cx2, Cy2, r2)
% 求两个圆的交点

clc

figure('name','Intersect point(s) of two circle');
theta = 0 : pi / 1000: 2 * pi;
x1 = r1 * cos( theta ) + Cx1;
y1 = r1 * sin( theta ) + Cy1;
plot( x1, y1, 'k');
hold on

x2 = r2 * cos( theta ) + Cx2;
y2 = r2 * sin( theta ) + Cy2;
plot( x2, y2, 'k');
hold off

% 求两圆的中心距
a = sqrt( ( Cx2 - Cx1 ) ^ 2 + ( Cy2 - Cy1 ) ^ 2 );

if  a > ( r1 + r2 )
   
    disp( ' There are no intersection points ! ' );
   
elseif a == ( r1 + r2 )
   
    disp( ' There is one intersection point !' );
   
else
   
    A = solve('( x1 - Cx1 ) ^ 2 + (y1 - Cy1 ) ^ 2 - r1 ^ 2','( x1 - Cx2 ) ^ 2 + ( y1 - Cy2 ) ^ 2 - r2 ^ 2');
    Px = subs( A.x1 );
    Py = subs( A.y1);
    disp( ' There are two intersection points ! ' );
    hold on
    plot( Px, Py, 'ro' )
    axis equal
    hold off

end