大约有 20,000 项符合查询结果（耗时：0.0457秒） [XML]
How to print instances of a class using print()?
...
>>> class Test:
... def __repr__(self):
... return "Test()"
... def __str__(self):
... return "member of Test"
...
>>> t = Test()
>>> t
Test()
>>> print(t)
member of Test
The __str__ method is what h...
What is the fastest way to get the value of π?
...ically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in.
22 Answers
...
Python __str__ and lists
...
Calling string on a python list calls the __repr__ method on each element inside. For some items, __str__ and __repr__ are the same. If you want that behavior, do:
def __str__(self):
...
def __repr__(self):
return self.__str__()
...
How can I group by date time column without taking time into consideration
I have a bunch of product orders and I'm trying to group by the date and sum the quantity for that date. How can I group by the month/day/year without taking the time part into consideration?
...
Is there a Python caching library?
...
From Python 3.2 you can use the decorator @lru_cache from the functools library.
It's a Last Recently Used cache, so there is no expiration time for the items in it, but as a fast hack it's very useful.
from functools import lru_cache
@lru_cache(maxsize=256)
def f(x):
...
Are parameters in strings.xml possible? [duplicate]
...
The order is not as important as you say. The numbers in the string is actually the order of the parameter. Depending on language you could have the numbers in different order.
– Flaxie
Jan ...
Comparison between Mockito vs JMockit - why is Mockito voted better than JMockit? [closed]
...s.
PowerMock uses custom class loaders (usually one per test class)
in order to generate modified versions
of the mocked classes. Such heavy use
of custom class loaders can lead to
conflicts with third-party libraries,
hence the need to sometimes use the
@PowerMockIgnore("package.to.be...
How to retrieve a module's path?
...
import a_module
print(a_module.__file__)
Will actually give you the path to the .pyc file that was loaded, at least on Mac OS X. So I guess you can do:
import os
path = os.path.abspath(a_module.__file__)
You can also try:
path ...
Purpose of Python's __repr__
...
__repr__ should return a printable representation of the object, most likely one of the ways possible to create this object. See official documentation here. __repr__ is more for developers while __str__ is for end users.
A ...
How to invoke the super constructor in Python?
...on-3.x the process has been simplified:
Python-2.x
class A(object):
def __init__(self):
print "world"
class B(A):
def __init__(self):
print "hello"
super(B, self).__init__()
Python-3.x
class A(object):
def __init__(self):
print("world")
class B(A):
def __init__(self):
print...