1 from numpy import *
   2 import pylab
   3 
   4 def mandelbrot( h,w, maxit=20 ):
   5         '''Returns an image of the Mandelbrot fractal of size (h,w).
   6         '''
   7         y,x = ogrid[ -1.4:1.4:h*1j, -2:0.8:w*1j ]
   8         c = x+y*1j
   9         z = c
  10         divtime = maxit + zeros(z.shape, dtype=int)
  11 
  12         for i in xrange(maxit):
  13                 z  = z**2 + c
  14                 diverge = z*conj(z) > 2**2            # who is diverging
  15                 div_now = diverge & (divtime==maxit)  # who is diverging now
  16                 divtime[div_now] = i                  # note when
  17                 z[diverge] = 2                        # avoid diverging too much
  18         
  19         return divtime
  20         
  21 pylab.imshow(mandelbrot(400,400))
  22 pylab.show()