这里的Python新手，很可能我在这里犯了一个愚蠢的错误。
在丢失大量头发并搜索了许多小时之后，我仍然无法将整个项目转换为python3。我有一个使用django框架制作的项目，它使用python 3.7，我想将其合并库放入我的应用程序。但是，由于pyshipping使用的是python 2.7，我认为这可能会导致兼容性问题。在回答this之后，我转换了整个项目，并尝试运行此文件binpack_simple.py。但这给了我一个我根本无法理解的错误。当我在项目iterpreter设置为python 2.7时使用pycharm终端运行此文件时，它运行得很好，但是当我将iterpreter设置为3.7时，它给了我以下错误
return _pyprofile._Utils(Profile).run(statement, filename, sort)
File "C:\Users\idadarklord\AppData\Local\Programs\Python\Python37\lib\profile.py", line 53, in run
prof.run(statement)
File "C:\Users\idadarklord\AppData\Local\Programs\Python\Python37\lib\cProfile.py", line 95, in run
return self.runctx(cmd, dict, dict)
File "C:\Users\idadarklord\AppData\Local\Programs\Python\Python37\lib\cProfile.py", line 100, in runctx
exec(cmd, globals, locals)
File "<string>", line 1, in <module>
File "C:/Users/idadarklord/PycharmProjects/untitled/pyshipping/binpack_simple.py", line 230, in test
bins, rest = binpack(packages)
File "C:/Users/idadarklord/PycharmProjects/untitled/pyshipping/binpack_simple.py", line 218, in binpack
return allpermutations(packages, bin, iterlimit)
File "C:/Users/idadarklord/PycharmProjects/untitled/pyshipping/binpack_simple.py", line 203, in allpermutations
trypack(bin, todo, bestpack)
File "C:/Users/idadarklord/PycharmProjects/untitled/pyshipping/binpack_simple.py", line 187, in trypack
bins, rest = packit(bin, packages)
File "C:/Users/idadarklord/PycharmProjects/untitled/pyshipping/binpack_simple.py", line 131, in packit
packages = sorted(originalpackages)
TypeError: '<' not supported between instances of 'Package' and 'Package'
这是我的文件。请让我知道我是否应该上传整个项目以进行澄清。
#!/usr/bin/env python
# encoding: utf-8
"""
binpack_simple.py
"""
from builtins import map
from builtins import range
from pyshipping.package import Package
from setuptools import setup, find_packages
from distutils.extension import Extension
import codecs
import time
import random
def packstrip(bin, p):
"""Creates a Strip which fits into bin.
Returns the Packages to be used in the strip, the dimensions of the strip as a 3-tuple
and a list of "left over" packages.
"""
# This code is somewhat optimized and somewhat unreadable
s = [] # strip
r = [] # rest
ss = sw = sl = 0 # stripsize
bs = bin.heigth # binsize
sapp = s.append # speedup
rapp = r.append # speedup
ppop = p.pop # speedup
while p and (ss <= bs):
n = ppop(0)
nh, nw, nl = n.size
if ss + nh <= bs:
ss += nh
sapp(n)
if nw > sw:
sw = nw
if nl > sl:
sl = nl
else:
rapp(n)
return s, (ss, sw, sl), r + p
def packlayer(bin, packages):
strips = []
layersize = 0
layerx = 0
layery = 0
binsize = bin.width
while packages:
strip, (sizex, stripsize, sizez), rest = packstrip(bin, packages)
if layersize + stripsize <= binsize:
packages = rest
if not strip:
# we were not able to pack anything
break
layersize += stripsize
layerx = max([sizex, layerx])
layery = max([sizez, layery])
strips.extend(strip)
else:
# Next Layer please
packages = strip + rest
break
return strips, (layerx, layersize, layery), packages
def packbin(bin, packages):
packages.sort()
layers = []
contentheigth = 0
contentx = 0
contenty = 0
binsize = bin.length
while packages:
layer, (sizex, sizey, layersize), rest = packlayer(bin, packages)
if contentheigth + layersize <= binsize:
packages = rest
if not layer:
# we were not able to pack anything
break
contentheigth += layersize
contentx = max([contentx, sizex])
contenty = max([contenty, sizey])
layers.extend(layer)
else:
# Next Bin please
packages = layer + rest
break
return layers, (contentx, contenty, contentheigth), packages
def packit(bin, originalpackages):
packedbins = []
packages = sorted(originalpackages)
while packages:
packagesinbin, (binx, biny, binz), rest = packbin(bin, packages)
if not packagesinbin:
# we were not able to pack anything
break
packedbins.append(packagesinbin)
packages = rest
# we now have a result, try to get a better result by rotating some bins
return packedbins, rest
# In newer Python versions these van be imported:
# from itertools import permutations
def product(*args, **kwds):
# product('ABCD', 'xy') --> Ax Ay Bx By Cx Cy Dx Dy
# product(range(2), repeat=3) --> 000 001 010 011 100 101 110 111
pools = list(map(tuple, args)) * kwds.get('repeat', 1)
result = [[]]
for pool in pools:
result = [x + [y] for x in result for y in pool]
for prod in result:
yield tuple(prod)
def permutations(iterable, r=None):
pool = tuple(iterable)
n = len(pool)
r = n if r is None else r
for indices in product(list(range(n)), repeat=r):
if len(set(indices)) == r:
yield tuple(pool[i] for i in indices)
class Timeout(Exception):
pass
def allpermutations_helper(permuted, todo, maxcounter, callback, bin, bestpack, counter):
if not todo:
return counter + callback(bin, permuted, bestpack)
else:
others = todo[1:]
thispackage = todo[0]
for dimensions in set(permutations((thispackage[0], thispackage[1], thispackage[2]))):
thispackage = Package(dimensions, nosort=True)
if thispackage in bin:
counter = allpermutations_helper(permuted + [thispackage], others, maxcounter, callback,
bin, bestpack, counter)
if counter > maxcounter:
raise Timeout('more than %d iterations tries' % counter)
return counter
def trypack(bin, packages, bestpack):
bins, rest = packit(bin, packages)
if len(bins) < bestpack['bincount']:
bestpack['bincount'] = len(bins)
bestpack['bins'] = bins
bestpack['rest'] = rest
if bestpack['bincount'] < 2:
raise Timeout('optimal solution found')
return len(packages)
def allpermutations(todo, bin, iterlimit=5000):
random.seed(1)
random.shuffle(todo)
bestpack = dict(bincount=len(todo) + 1)
try:
# First try unpermuted
trypack(bin, todo, bestpack)
# now try permutations
allpermutations_helper([], todo, iterlimit, trypack, bin, bestpack, 0)
except Timeout:
pass
return bestpack['bins'], bestpack['rest']
def binpack(packages, bin=None, iterlimit=5000):
"""Packs a list of Package() objects into a number of equal-sized bins.
Returns a list of bins listing the packages within the bins and a list of packages which can't be
packed because they are to big."""
if not bin:
bin = Package("600x400x400")
return allpermutations(packages, bin, iterlimit)
def test():
fd = open('small.txt')
vorher = 0
nachher = 0
start = time.time()
for line in fd:
packages = [Package(pack) for pack in line.strip().split()]
if not packages:
continue
bins, rest = binpack(packages)
if rest:
print(("invalid data", rest, line))
else:
vorher += len(packages)
nachher += len(bins)
# print((time.time() - start))
print((vorher, nachher, float(nachher) / vorher * 100))
#
if __name__ == '__main__':
import cProfile
cProfile.run('test()')
# packlayer(bin, packages)
Here是指向项目内部文件的在线链接。
答案 0 :(得分：3)
在Python 3中，对__cmp__方法has been removed的支持。如果要比较两个实例，则需要为该类提供一个__lt__方法。原始Package.__cmp__的代码为here。
新方法可能类似于：
def __lt__(self, other):
return self.volume < other.volume
但是显然您应该对此进行彻底的测试。
答案 1 :(得分：0)
您需要将“ volume”设置为排序关键字，这意味着：
更改：
packages.sort()
packages = sorted(originalpackages)
收件人：
packages.sort(key=lambda x: x.volume)
packages = sorted(originalpackages, key=lambda x: x.volume)
因此，您无需手动更改任何软件包内部代码。