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eykd/python_evolution.py

Created January 20, 2011 21:18
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Profiling the factorial implementations at http://metaleks.net/programming/the-evolution-of-a-python-programmer/comment-page-1 with results for factorial(10) run 100,000 times.
Raw
python_evolution.py
# -*- coding: utf-8 -*-
"""Profiling The Evolution of the Python Programmer
Based on the code offered in good humor at
<http://metaleks.net/programming/the-evolution-of-a-python-programmer>.
I thought it would be fun to profile the various approaches to a
factorial implementation offered by Aleks. My attempt below.
I couldn't profile the EXPERT PROGRAMMERS or the Unix Programmer, as I
am missing their external implementations. ;)
According to my results, the first-year Pascal student wins by a thin
margin over the first-year C student.
"""
import sys
import hotshot
import hotshot, hotshot.stats
from cStringIO import StringIO
to_profile = []
profile_times = 100000
def profile(func):
buffer = StringIO()
def profile_func():
stdout = sys.stdout
stderr = sys.stderr
sys.stdout = buffer
sys.stderr = buffer
for x in xrange(profile_times):
func()
sys.stdout = stdout
sys.stderr = stderr
to_profile.append((func.__name__, profile_func))
return func
n = 10
def tailcall(g):
'''
Version of tail_recursion decorator using stack-frame inspection.
from:
http://code.activestate.com/recipes/496691-new-tail-recursion-decorator/
'''
loc_vars ={"in_loop":False,"cnt":0}
def result(*args, **kwd):
if not loc_vars["in_loop"]:
loc_vars["in_loop"] = True
while 1:
tc = g(*args,**kwd)
try:
qual, args, kwd = tc
if qual == 'continue':
continue
except TypeError:
loc_vars["in_loop"] = False
return tc
else:
f = sys._getframe()
if f.f_back and f.f_back.f_back and \
f.f_back.f_back.f_code == f.f_code:
return ('continue',args, kwd)
return g(*args,**kwd)
return result
@profile
def newbie():
def factorial(x):
if x == 0:
return 1
else:
return x * factorial(x - 1)
print factorial(n)
@profile
def first_year_pascal():
def factorial(x):
result = 1
i = 2
while i <= x:
result = result * i
i = i + 1
return result
print factorial(n)
@profile
def first_year_c():
def fact(x): #{
result = i = 1;
while (i <= x): #{
result *= i;
i += 1;
#}
return result;
#}
print(fact(n))
@profile
def first_year_sicp():
@tailcall
def fact(x, acc=1):
if (x > 1): return (fact((x - 1), (acc * x)))
else: return acc
print(fact(n))
@profile
def first_year_python():
def Factorial(x):
res = 1
for i in xrange(2, x + 1):
res *= i
return res
print Factorial(n)
@profile
def lazy_python_programmer():
def fact(x):
return x > 1 and x * fact(x - 1) or 1
print fact(n)
@profile
def lazier_python_programmer():
def fact(x):
return x > 1 and x * fact(x - 1) or 1
print fact(n)
@profile
def python_expert_programmer():
fact = lambda x: reduce(int.__mul__, xrange(2, x + 1), 1)
print fact(n)
@profile
def python_hacker():
import sys
@tailcall
def fact(x, acc=1):
if x: return fact(x.__sub__(1), acc.__mul__(x))
return acc
sys.stdout.write(str(fact(n)) + '\n')
### No c_math implementation!
# @profile
# def expert_programmer():
# from c_math import fact
# print fact(n)
### No c_maths implementation!
# @profile
# def british_expert_programmer():
# from c_maths import fact
# print fact(n)
@profile
def web_designer():
def factorial(x):
#-------------------------------------------------
#--- Code snippet from The Math Vault ---
#--- Calculate factorial (C) Arthur Smith 1999 ---
#-------------------------------------------------
result = str(1)
i = 1 #Thanks Adam
while i <= x:
#result = result * i #It's faster to use *=
#result = str(result * result + i)
#result = int(result *= i) #??????
result = str(int(result) * i)
#result = int(str(result) * i)
i = i + 1
return result
print factorial(n)
### No factorial implementation!
# @profile
# def unix_programmer():
# import os
# def fact(x):
# os.system('factorial ' + str(x))
# fact(n)
@profile
def windows_programmer():
NULL = None
def CalculateAndPrintFactorialEx(dwNumber,
hOutputDevice,
lpLparam,
lpWparam,
lpsscSecurity,
*dwReserved):
if lpsscSecurity != NULL:
return NULL #Not implemented
dwResult = dwCounter = 1
while dwCounter <= dwNumber:
dwResult *= dwCounter
dwCounter += 1
hOutputDevice.write(str(dwResult))
hOutputDevice.write('\n')
return 1
import sys
CalculateAndPrintFactorialEx(6, sys.stdout, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
@profile
def enterprise_programmer():
def new(cls, *args, **kwargs):
return cls(*args, **kwargs)
class Number(object):
pass
class IntegralNumber(int, Number):
def toInt(self):
return new (int, self)
class InternalBase(object):
def __init__(self, base):
self.base = base.toInt()
def getBase(self):
return new (IntegralNumber, self.base)
class MathematicsSystem(object):
def __init__(self, ibase):
Abstract
@classmethod
def getInstance(cls, ibase):
try:
cls.__instance
except AttributeError:
cls.__instance = new (cls, ibase)
return cls.__instance
class StandardMathematicsSystem(MathematicsSystem):
def __init__(self, ibase):
if ibase.getBase() != new (IntegralNumber, 2):
raise NotImplementedError
self.base = ibase.getBase()
def calculateFactorial(self, target):
result = new (IntegralNumber, 1)
i = new (IntegralNumber, 2)
while i <= target:
result = result * i
i = i + new (IntegralNumber, 1)
return result
print StandardMathematicsSystem.getInstance(new (InternalBase, new (IntegralNumber, 2))).calculateFactorial(new (IntegralNumber, 6))
if __name__ == "__main__":
for name, func in to_profile:
print '=' * 20, name
prof = hotshot.Profile("quick_%s.prof" % name)
prof.runcall(func)
prof.close()
stats = hotshot.stats.load("quick_%s.prof" % name)
stats.strip_dirs()
stats.sort_stats('time', 'calls')
stats.print_stats(20)
Raw
python_evolution_results.txt
Results run on a MacBook 2GHz Intel Core 2 Duo.
==================== newbie
1200001 function calls (200001 primitive calls) in 1.788 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
1100000/100000 0.939 0.000 0.939 0.000 python_evolution.py:98(factorial)
100000 0.760 0.000 1.699 0.000 python_evolution.py:96(newbie)
1 0.089 0.089 1.788 1.788 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== first_year_pascal
200001 function calls in 0.871 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 0.557 0.000 0.812 0.000 python_evolution.py:106(first_year_pascal)
100000 0.255 0.000 0.255 0.000 python_evolution.py:108(factorial)
1 0.059 0.059 0.871 0.871 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== first_year_c
200001 function calls in 0.875 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 0.564 0.000 0.818 0.000 python_evolution.py:118(first_year_c)
100000 0.254 0.000 0.254 0.000 python_evolution.py:120(fact)
1 0.057 0.057 0.875 0.875 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== first_year_sicp
2200001 function calls (1300001 primitive calls) in 7.496 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
1000000/100000 4.143 0.000 5.985 0.000 python_evolution.py:48(result)
1000000 1.842 0.000 3.651 0.000 python_evolution.py:132(fact)
100000 1.208 0.000 7.396 0.000 python_evolution.py:130(first_year_sicp)
100000 0.203 0.000 0.203 0.000 python_evolution.py:39(tailcall)
1 0.100 0.100 7.496 7.496 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== first_year_python
200001 function calls in 0.908 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 0.562 0.000 0.849 0.000 python_evolution.py:138(first_year_python)
100000 0.287 0.000 0.287 0.000 python_evolution.py:140(Factorial)
1 0.059 0.059 0.908 0.908 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== lazy_python_programmer
1100001 function calls (200001 primitive calls) in 1.697 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
1000000/100000 0.885 0.000 0.885 0.000 python_evolution.py:150(fact)
100000 0.719 0.000 1.604 0.000 python_evolution.py:148(lazy_python_programmer)
1 0.093 0.093 1.697 1.697 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== lazier_python_programmer
1100001 function calls (200001 primitive calls) in 1.674 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
1000000/100000 0.868 0.000 0.868 0.000 python_evolution.py:157(fact)
100000 0.716 0.000 1.584 0.000 python_evolution.py:155(lazier_python_programmer)
1 0.089 0.089 1.674 1.674 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== python_expert_programmer
200001 function calls in 1.197 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 0.583 0.000 1.132 0.000 python_evolution.py:162(python_expert_programmer)
100000 0.549 0.000 0.549 0.000 python_evolution.py:164(<lambda>)
1 0.064 0.064 1.197 1.197 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== python_hacker
2400001 function calls (1400001 primitive calls) in 8.591 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
1100000/100000 4.948 0.000 7.326 0.000 python_evolution.py:48(result)
1100000 2.378 0.000 4.537 0.000 python_evolution.py:171(fact)
100000 0.958 0.000 8.485 0.000 python_evolution.py:168(python_hacker)
100000 0.201 0.000 0.201 0.000 python_evolution.py:39(tailcall)
1 0.106 0.106 8.591 8.591 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== web_designer
200001 function calls in 4.118 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 3.397 0.000 3.397 0.000 python_evolution.py:192(factorial)
100000 0.642 0.000 4.039 0.000 python_evolution.py:190(web_designer)
1 0.079 0.079 4.118 4.118 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== windows_programmer
200001 function calls in 0.937 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 0.483 0.000 0.483 0.000 python_evolution.py:221(CalculateAndPrintFactorialEx)
100000 0.367 0.000 0.850 0.000 python_evolution.py:218(windows_programmer)
1 0.087 0.087 0.937 0.937 python_evolution.py:21(profile_func)
0 0.000 0.000 profile:0(profiler)
==================== enterprise_programmer
2800001 function calls (2400001 primitive calls) in 23.460 CPU seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
100000 17.308 0.000 23.345 0.000 python_evolution.py:240(enterprise_programmer)
1500000/1100000 2.323 0.000 3.259 0.000 python_evolution.py:242(new)
100000 1.010 0.000 1.473 0.000 python_evolution.py:277(calculateFactorial)
100000 0.812 0.000 2.154 0.000 python_evolution.py:263(getInstance)
100000 0.376 0.000 0.983 0.000 python_evolution.py:272(__init__)
100000 0.376 0.000 0.376 0.000 python_evolution.py:259(MathematicsSystem)
200000 0.251 0.000 0.466 0.000 python_evolution.py:256(getBase)
100000 0.224 0.000 0.224 0.000 python_evolution.py:271(StandardMathematicsSystem)
100000 0.176 0.000 0.176 0.000 python_evolution.py:248(IntegralNumber)
100000 0.163 0.000 0.404 0.000 python_evolution.py:253(__init__)
100000 0.145 0.000 0.241 0.000 python_evolution.py:249(toInt)
100000 0.130 0.000 0.130 0.000 python_evolution.py:252(InternalBase)
1 0.115 0.115 23.460 23.460 python_evolution.py:21(profile_func)
100000 0.050 0.000 0.050 0.000 python_evolution.py:245(Number)
0 0.000 0.000 profile:0(profiler)
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