// This image was created with the following Python source code and then recolored and converted to SVG in Adobe Illustrator.  from pyx import canvas,path,color from math import * from random import seed,random seed(12345)   npoints = 100 radius = 0.05 exclusion = 0.2     # prevent points from being too close scale = 5  def dist2(p,q):     return (p[0]-q[0])**2 + (p[1]-q[1])**2   points = [] while len(points) < 100:     p = (random()*scale,random()*scale)     if points:         nn = min(dist2(p,q)**0.5 for q in points)         if nn < exclusion:             continue     points.append(p)  def neighbors(p,q):     c = ((p[0]+q[0])/2,(p[1]+q[1])/2)     dd = dist2(p,c)     for r in points:         if r != p and r != q and dist2(r,c) < dd:             return False     return True   c = canvas.canvas()   def edge(p,q):     c.stroke(path.line(p[0],p[1],q[0],q[1]),              [color.rgb.black])   def point(p):     c.fill(path.circle(p[0],p[1],radius),[color.rgb.red])   for p in points:     for q in points:         if p < q and neighbors(p,q):             edge(p,q)   for p in points:     point(p)   c.writePDFfile("Gabriel_graph")