MATLAB: Check the overlap between circles

circlemathematicsMATLABoverlap

This code is to check the overlap between circles, is it possible to do this without for loop?
function pairs = checkOverlap(circles, rads)
%circles : circles matrix [x, y]; each row represents a circle;
rads : radius of each circle
ncircles = size(circles,1);
for i=1:ncircles -1
% distances between circles:
dx = bsxfun(@minus, circles(i,1), circles(i+1,1));
dy = bsxfun(@minus, circles(i,2), circles(i+1,2));
sumr(i) = bsxfun(@plus, rads(i,1), rads(i+1,1));
% distance between centers:
dist(i) = sqrt(dx.^2 + dy.^2);
end
% pairs that have overlap:
pairs = find(dist < sumr);
end
Run:
circles = rand(5, 2); % 5 circles
rads = rand(5,1); % 5 radius
Isoverlap = checkOverlap(circles, rads);

Best Answer

EDIT
rad2 = rads(:) + rads(:)';
dxy = sqrt( (xy(:,1) - xy(:,1)').^2 + (xy(:,2) - xy(:,2)').^2 );
lo = dxy <= rad2;
lo(1:size(xy,1)+1:end) = false;
intersecting_circles = find(any(lo,2));
Related Question