自内联 python 代码。 (现在有了 MCVE!)

Self-inlining python code. (Now with MCVE!)

我有一个用 python 编写的程序,其中用户提供命令行参数来说明哪些统计信息、哪些组合应该对某些数据进行处理。

最初我编写的代码会采用 X 组合中的 N 个统计数据并计算结果 - 但是,我发现如果我自己编写代码来执行特定的统计数据组合,它总是会快得多。然后我编写了代码来编写 python 如果我手动完成的话我会写的代码,然后执行它,这非常有效。理想情况下,我想找到一种方法来获得与 python 重写循环时相同的性能,但以某种不需要我的所有函数都是字符串的方式来实现!

以下代码是用于说明问题的最小完整可验证示例。

import time
import argparse
import collections

parser = argparse.ArgumentParser(formatter_class=argparse.RawTextHelpFormatter,
    description="Demonstration that it is sometimes much faster to use exec() than to not.")
parser.add_argument("--stat", nargs='+', metavar='', action='append',
    help='Supply a list of stats to run here. You can use --stat more than once to make multiple groups.')
args = parser.parse_args()

allStats = {}
class stat1:
    def __init__(self):
        def process(someValue):
            return someValue**3
        self.calculate = process
allStats['STAT1'] = stat1()

class stat2:
    def __init__(self):
        def process(someValue):
            return someValue*someValue
        self.calculate = process
allStats['STAT2'] = stat2()

class stat3:
    def __init__(self):
        def process(someValue):
            return someValue+someValue
        self.calculate = process
allStats['STAT3'] = stat3()

allStatsString = {}
allStatsString['STAT1'] = 'STAT1 = someValue**3'
allStatsString['STAT2'] = 'STAT2 = someValue*someValue'
allStatsString['STAT3'] = 'STAT3 = someValue+someValue'

stats_to_run = set()                                                   # stats_to_run is a set of the stats the user wants to run, irrespective of grouping.
data = [collections.defaultdict(int) for x in range(0,len(args.stat))] # data is a list of dictionaries. One dictionary for each --stat group.
for group in args.stat:
    stats_to_run.update(group)
    for stat in group:
        if stat not in allStats.keys():
            print "I'm sorry Dave, I'm afraid I can't do that."; exit()

loops = 9000000
option = 1
startTime = time.time()
if option == 1:
    results = dict.fromkeys(stats_to_run)
    for someValue in xrange(0,loops):
        for analysis in stats_to_run:
            results[analysis] = allStats[analysis].calculate(someValue)
        for a, analysis in enumerate(args.stat):
            data[a][tuple([ results[stat] for stat in analysis ])] += 1

elif option == 2:
    for someValue in xrange(0,loops):
        STAT1 = someValue**3
        STAT2 = someValue*someValue
        STAT3 = someValue+someValue        
        data[0][(STAT1,STAT2)] += 1  # Store the first result group
        data[1][(STAT3,)] += 1       # Store the second result group

else:
    execute = 'for someValue in xrange(0,loops):'
    for analysis in stats_to_run:
        execute += '\n    ' + allStatsString[analysis]
    for a, analysis in enumerate(args.stat):
        if len(analysis) == 1: 
            execute += '\n    data[' + str(a) + '][('+ analysis[0] + ',)] += 1'
        else: 
            execute += '\n    data[' + str(a) + '][('+ ','.join(analysis) + ')] += 1'
    print execute
    exec(execute)

## This bottom bit just adds all these numbers up so we get a single value to compare the different methods with (to make sure they are the same)
total = 0
for group in data:
    for stats in group:
        total += sum(stats)
print total
print time.time() - startTime

如果使用参数python test.py --stat STAT1 STAT2 --stat STAT3执行脚本,那么平均:

我认为您只是想避免重复计算相同的统计数据。试试这个。请注意,我使用的是 docopt,因此我使用逗号分隔的列表。您已经以某种方式弄清楚了,但没有告诉我们如何做,所以不用担心 - 这并不重要。 parse_args 中我构建一组统计名称的代码可能是关键。

"""
Usage: calcstats (--analyses <STAT>,...) ... <file> ...

Options:
    <file>                    One or more input filenames
    -a,--analyses <STAT> ...  One or more stat names to compute

"""

import docopt
import time

_Sequence = 0
_Results = {}

def compute_stat(name):
    global _Sequence, _Results

    print("Performing analysis: {}".format(name))
    time.sleep(1)
    _Sequence += 1
    _Results[name] = _Sequence

def display_results(groups):
    global _Results

    groupnum = 1
    for grp in groups:
        print("*** Group {}:".format(groupnum))
        for stat in grp:
            print("\t{}: {}".format(stat, _Results[stat]))
        print("\n")

def parse_args():
    args = docopt.docopt(__doc__)
    args['--analyses'] = [stat.split(',') for stat in args['--analyses']]

    stat_set = set()
    stat_set.update(*args['--analyses'])
    args['STATS.unique'] = stat_set

    return args

def perform_analyses(stat_set):
    for stat in stat_set:
        compute_stat(stat)

if __name__ == '__main__':
    args = parse_args()
    perform_analyses(args['STATS.unique'])
    display_results(args['--analyses'])