相关疑难解决方法(0)

我需要从特定的面/顶点列表计算最小值,最大值和平均值.我尝试使用Numpy来优化这种计算,但没有成功.

这是我的测试用例:

#!/usr/bin/python
# -*- coding: iso-8859-15 -*-
'''
Module Started 22 févr. 2013
@note: test case comparaison numpy vs python
@author: Python4D/damien
'''

import numpy as np
import time


def Fnumpy(vertices):
  np_vertices=np.array(vertices)
  _x=np_vertices[:,:,0]
  _y=np_vertices[:,:,1]
  _z=np_vertices[:,:,2]
  _min=[np.min(_x),np.min(_y),np.min(_z)]
  _max=[np.max(_x),np.max(_y),np.max(_z)]
  _mean=[np.mean(_x),np.mean(_y),np.mean(_z)]
  return _mean,_max,_min

def Fpython(vertices):
  list_x=[item[0] for sublist in vertices for item in sublist]
  list_y=[item[1] for sublist in vertices for item in sublist]
  list_z=[item[2] for sublist in vertices for item in sublist]
  taille=len(list_x)
  _mean=[sum(list_x)/taille,sum(list_y)/taille,sum(list_z)/taille]
  _max=[max(list_x),max(list_y),max(list_z)]
  _min=[min(list_x),min(list_y),min(list_z)]    
  return _mean,_max,_min

if __name__=="__main__":
  vertices=[[[1.1,2.2,3.3,4.4]]*4]*1000000
  _t=time.clock() …