函数的补丁datetime和strptime性能的提高
monkeytime的Python项目详细描述
补丁datetime使用更快的strtime实现。
当格式字符串使用填充指令时，此仅改进了strtime。
这是受支持指令的列表（迄今为止最常见）：
SUPPORTED_DIRECTIVES = ('%d', '%m', '%Y', '%H', '%M', '%S', '%f')
请致电：
datetime.supported_strptime(format_string) # True if supported, False otherwise
平均来说，比stdlib版本快4倍，比stdlib版本快40倍 使用pypy时！
用法：
# insert this one line
from monkeytime import datetime
# Done migrating code to monkeytime!
from datetime import datetime
# Call it once with the specific format string
# It will build a new function to quickly parse the string, then run it on
# the string you passed it.
dt = datetime.strptime('2014-05-30T12:14:15.123456', '%Y-%m-%dT%H:%M:%S.%f')
# Now, whenever you use that format again, it will use the function it
# built already! All constructed functions are memoized.
# Since we usually only use one or two formats in our code to parse logs
# and such, the performance of constructing it is negligible.
您只需要一行“from monkeytime import datetime”，然后 strtime性能将显著提高。
确保它位于“from datetime import datetime”导入行之上！
性能示例：
$ python timeit_test.py
Testing builtin strptime
testing ('2015-01-02 03:04:05.001234', '%Y-%m-%d %H:%M:%S.%f')
6.80288290977 seconds
testing ('05-06 12:15:18', '%m-%d %H:%M:%S')
5.81049013138 seconds
testing ('2010', '%Y')
4.29107117653 seconds
testing ('1905/08/05', '%Y/%m/%d')
4.92634987831 seconds
testing ('14:05:03.123456', '%H:%M:%S.%f')
5.6812889576 seconds
Testing monkeytime strptime
testing ('2015-01-02 03:04:05.001234', '%Y-%m-%d %H:%M:%S.%f')
1.83126211166 seconds
testing ('05-06 12:15:18', '%m-%d %H:%M:%S')
1.5586848259 seconds
testing ('2010', '%Y')
0.877351999283 seconds
testing ('1905/08/05', '%Y/%m/%d')
1.24154901505 seconds
testing ('14:05:03.123456', '%H:%M:%S.%f')
1.3871409893 seconds
3.714860 times as fast
3.727816 times as fast
4.890935 times as fast
3.967906 times as fast
4.095682 times as fast
Average: 4.079440 times as fast
$ pypy timeit_test.py
Testing builtin strptime
testing ('2015-01-02 03:04:05.001234', '%Y-%m-%d %H:%M:%S.%f')
2.19319605827 seconds
testing ('05-06 12:15:18', '%m-%d %H:%M:%S')
1.60669994354 seconds
testing ('2010', '%Y')
0.858637809753 seconds
testing ('1905/08/05', '%Y/%m/%d')
1.19449591637 seconds
testing ('14:05:03.123456', '%H:%M:%S.%f')
1.38721394539 seconds
Testing monkeytime strptime
testing ('2015-01-02 03:04:05.001234', '%Y-%m-%d %H:%M:%S.%f')
0.0362730026245 seconds
testing ('05-06 12:15:18', '%m-%d %H:%M:%S')
0.0450730323792 seconds
testing ('2010', '%Y')
0.0332229137421 seconds
testing ('1905/08/05', '%Y/%m/%d')
0.0321681499481 seconds
testing ('14:05:03.123456', '%H:%M:%S.%f')
0.0355319976807 seconds
60.463593 times as fast
35.646591 times as fast
25.844747 times as fast
37.132876 times as fast
39.041260 times as fast
Average: 39.625813 times as fast
欢迎加入QQ群-->： 979659372
