本文实例讲述了python定时执行指定函数的方法。分享给大家供大家参考。具体实现方法如下:
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# time a function using time.time() and the a @ function decorator # tested with Python24 vegaseat 21aug2005 import time def print_timing(func): def wrapper( * arg): t1 = time.time() res = func( * arg) t2 = time.time() print '%s took %0.3f ms' % (func.func_name, (t2 - t1) * 1000.0 ) return res return wrapper # declare the @ decorator just before the function, invokes print_timing() @print_timing def getPrimeList(n): """ returns a list of prime numbers from 2 to < n using a sieve algorithm""" if n < 2 : return [] if n = = 2 : return [ 2 ] # do only odd numbers starting at 3 s = range ( 3 , n + 1 , 2 ) # n**0.5 may be slightly faster than math.sqrt(n) mroot = n * * 0.5 half = len (s) i = 0 m = 3 while m < = mroot: if s[i]: j = (m * m - 3 ) / / 2 s[j] = 0 while j < half: s[j] = 0 j + = m i = i + 1 m = 2 * i + 3 return [ 2 ] + [x for x in s if x] if __name__ = = "__main__" : print "prime numbers from 2 to <10,000,000 using a sieve algorithm" primeList = getPrimeList( 10000000 ) time.sleep( 2.5 ) """ my output --> prime numbers from 2 to <10,000,000 using a sieve algorithm getPrimeList took 4750.000 ms """ |
希望本文所述对大家的Python程序设计有所帮助。