beginchar("C",em#,5cap#/7,0dth#); "Sigma"; path p[]; save ww,hh,dd; ww = w/10; hh = h/5; b := ww; x0 = x4 = 8ww; y4 = 10hh - y0 = .5hh; y2 = 5hh; x2 = ww; p1 = z0{left}..{down}z2; p2 = z2{down}..{right}z4; z5 = point .25 of p1; z1 = point .5 of p1; z6 = point .75 of p1; z7 = point .25 of p2; z3 = point .5 of p2; z8 = point .75 of p2; x9 = x5; y9 = y2; y10 = .5[y6,y1]; x10 = x0; y11 = .5[y7,y3]; x11 = x0; penpos0(b,90); penpos5(.6b,90); penpos1(1.7b,120); penpos6(.6b,150); penpos2(1.7b,180); penpos7(.6b,210); penpos3(1.7b,240); penpos8(.6b,270); penpos4(b,270); penstroke z0e{left}..z5e..z1e..z6e..{down}z2e{down}..z7e..z3e.. z8e..{right}z4e; pickup pencircle scaled b; drawdot z0; drawdot z4; pickup pencircle scaled .4pt; draw z3{up}..z9..{up}z10; draw z1{down}..z9..{down}z11; draw fullcircle scaled .5b shifted (z10); draw fullcircle scaled .5b shifted (z11); endchar;