function[V]=vort2D(xy0,xyc,gamma)

if size(xy0,1) > 1
    xyc = repmat(xyc,size(xy0,1),1);
end

%V = gamma/2/pi*[0 1; -1 0]*(xyc-xy0)'/sum((xyc-xy0).^2,2);
V = sum(repmat(gamma./sum((xyc-xy0).^2,2)/2/pi,1,2)'.*([0 1; -1 0]*(xyc-xy0)'),2);

end