% Witch of Agnesi
% Copyright (c) Christian Obrecht 2002

box(-5,-1,5,3)

O = point(0,0)
J = point(0,1)
c = circle(J,1)
l = line(point(0,2),0:)

trace(t,.1,179.9)
{
    L = line(O,t:)
    O M intersection(L,c)
    P = intersection(L,l)
    point(abscissa(P),ordinate(M))
}

draw(O) ; draw(line(O,0:),dotted)

t = 50
L = line(O,t:)
O M intersection(L,c)
P = intersection(L,l)
N = point(abscissa(P),ordinate(M))

thickness(.5) ; style(dashed)
draw(c) ; draw(l) ; draw(L,dashed,halfline)
draw(segment(M,N)) ; draw(segment(P,N))