def mandelbrot(z,maxiter):
    c = z
    for n in range(maxiter):
        if abs(z) > 2:
            return n
        z = z*z + c
    return maxiter
 
def mandelbrot_set(xmin,xmax,ymin,ymax,width,height,maxiter):
    r1 = np.linspace(xmin, xmax, width)
    r2 = np.linspace(ymin, ymax, height)
    return (r1,r2,[mandelbrot(complex(r, i),maxiter) for r in r1 for i in r2])
 
%timeit mandelbrot_set(-2.0,0.5,-1.25,1.25,1000,1000,80)

• https://www.ibm.com/developerworks/community/blogs/jfp/entry/How_To_Compute_Mandelbrodt_Set_Quickly?lang=en