大约有 5,685 项符合查询结果（耗时：0.0227秒） [XML]
Convert a list to a dictionary in Python
Let's say I have a list a in Python whose entries conveniently map to a dictionary. Each even element represents the key to the dictionary, and the following odd element is the value
...
How can I convert a datetime object to milliseconds since epoch (unix time) in Python?
I have a Python datetime object that I want to convert to unix time, or seconds/milliseconds since the 1970 epoch.
13 Ans...
Alphabet range in Python
...']
Other helpful string module features:
>>> help(string) # on Python 3
....
DATA
ascii_letters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
ascii_lowercase = 'abcdefghijklmnopqrstuvwxyz'
ascii_uppercase = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
digits = '0123456789'
...
Catch multiple exceptions in one line (except block)
...
From Python Documentation:
An except clause may name multiple exceptions as a parenthesized tuple, for example
except (IDontLikeYouException, YouAreBeingMeanException) as e:
pass
Or, for Python 2 only:
except (IDontLi...
Checking a Python module version at runtime
Many third-party Python modules have an attribute which holds the version information for the module (usually something like module.VERSION or module.__version__ ), however some do not.
...
Windows path in Python
...the correct configuration for your OS:
os.path.join(mydir, myfile)
From python 3.4 you can also use the pathlib module. This is equivelent to the above:
pathlib.Path(mydir, myfile)
or
pathlib.Path(mydir) / myfile
sha...
How can I multiply all items in a list together with Python?
...
Python 3: use functools.reduce:
>>> from functools import reduce
>>> reduce(lambda x, y: x*y, [1,2,3,4,5,6])
720
Python 2: use reduce:
>>> reduce(lambda x, y: x*y, [1,2,3,4,5,6])
720
For compa...
Print in one line dynamically
...
Change print item to:
print item, in Python 2.7
print(item, end=" ") in Python 3
If you want to print the data dynamically use following syntax:
print(item, sep=' ', end='', flush=True) in Python 3
...
How do I change the working directory in Python?
... the current working directory in the parent process. This is true of the Python interpreter as well. You cannot use os.chdir() to change the CWD of the calling process.
share
|
improve this answe...
What is the correct syntax for 'else if'?
I'm a new Python programmer who is making the leap from 2.6.4 to 3.1.1. Everything has gone fine until I tried to use the 'else if' statement. The interpreter gives me a syntax error after the 'if' in 'else if' for a reason I can't seem to figure out.
...