付属しているサンプルは現在のnumpyのバージョンに適応していないようです。
独自に動作確認したサンプルを下記に記載します。

import os, pygame
from pygame.locals import *

try:
    from numpy import *
    from numpy.oldnumeric import *
    from numpy.random import *
except ImportError:
    raise SystemExit('This example requires Numeric and the pygame surfarray module')

pygame.surfarray.use_arraytype('numpy')

timer = 0
def stopwatch(message = None):
    "simple routine to time python code"
    global timer
    if not message:
        timer = pygame.time.get_ticks()
        return
    now = pygame.time.get_ticks()
    runtime = (now - timer)/1000.0 + .001
    print ("%s %s %s" %
           (message, runtime, ('seconds	(%.2ffps)'%(1.0/runtime))))
    timer = now



def VertGrad3D(surf, topcolor, bottomcolor):
    "creates a new 3d vertical gradient array"
    topcolor = array(topcolor, copy=0)
    bottomcolor = array(bottomcolor, copy=0)
    diff = bottomcolor - topcolor
    width, height = surf.get_size()
    # create array from 0.0 to 1.0 triplets
    column = arange(height, dtype=Float)/height
    column = repeat(column[:, newaxis], [3], 1)
    # create a single column of gradient
    column = topcolor + (diff * column).astype(Int)
    # make the column a 3d image column by adding X
    column = column.astype(UnsignedInt8)[newaxis,:,:]
    #3d array into 2d array
    column = pygame.surfarray.map_array(surf, column)
    # stretch the column into a full image
    return resize(column, (width, height))



def DisplayGradient(surf):
    "choose random colors and show them"
    stopwatch()
    colors = randint(0, 255, (2, 3))
    grade = VertGrad3D(surf, colors[0], colors[1])
    pygame.surfarray.blit_array(surf, grade)
    pygame.display.flip()
    stopwatch('Gradient:')



def main():
    pygame.init()
    size = 600, 400
    os.environ['SDL_VIDEO_CENTERED'] = '1'
    screen = pygame.display.set_mode(size, NOFRAME, 0)

    pygame.event.set_blocked(MOUSEMOTION) #keep our queue cleaner
    pygame.time.set_timer(USEREVENT, 500)

    while 1:
        event = pygame.event.wait()
        if event.type in (QUIT, KEYDOWN, MOUSEBUTTONDOWN):
            break
        elif event.type == USEREVENT:
            DisplayGradient(screen)



if __name__ == '__main__': main()