%CIRCLE.M plots a circle
% Input: XY Coords, Radius
function circle(y,x,r,c)
if nargin~=4
    c=['br'];
end
t=0:0.01:2*pi;
if isfinite(r)
    xp=x+r*cos(t);
    yp=y+r*sin(t);
    if r>0
        plot(yp,xp,c(1))
    else
        plot(yp,xp,c(2))
    end        
else
    disp('Note: Plot SKIPPED b/c r is not FINITE')
end
