大约有 12,000 项符合查询结果（耗时：0.0193秒） [XML]
Instance variables vs. class variables in Python
I have Python classes, of which I need only one instance at runtime, so it would be sufficient to have the attributes only once per class and not per instance. If there would be more than one instance (which won't happen), all instance should have the same configuration. I wonder which of the follow...
How to loop backwards in python? [duplicate]
...hould really be using xrange instead. So,
xrange(10, 0, -1)
Note for Python 3 users: There are no separate range and xrange functions in Python 3, there is just range, which follows the design of Python 2's xrange.
sh...
Numpy: find first index of value fast
...umba (1) is the easiest way until numpy implements it. If you use anaconda python distribution it should already be installed.
The code will be compiled so it will be fast.
@jit(nopython=True)
def find_first(item, vec):
"""return the index of the first occurence of item in vec"""
for i in x...
Some built-in to pad a list in python
...
I think this approach is more visual and pythonic.
a = (a + N * [''])[:N]
share
|
improve this answer
|
follow
|
...
Solving “Who owns the Zebra” programmatically?
...
Here's a solution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swed...
How do I capture SIGINT in Python?
I'm working on a python script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl + C signal, and I'd like to do some cleanup.
...
How do Python's any and all functions work?
I'm trying to understand how the any() and all() Python built-in functions work.
8 Answers
...
Checking whether a variable is an integer or not [duplicate]
...If you need to do this, do
isinstance(<var>, int)
unless you are in Python 2.x in which case you want
isinstance(<var>, (int, long))
Do not use type. It is almost never the right answer in Python, since it blocks all the flexibility of polymorphism. For instance, if you subclass int, y...
How can I implement a tree in Python?
...
anytree
I recommend https://pypi.python.org/pypi/anytree (I am the author)
Example
from anytree import Node, RenderTree
udo = Node("Udo")
marc = Node("Marc", parent=udo)
lian = Node("Lian", parent=marc)
dan = Node("Dan", parent=udo)
jet = Node("Jet", parent...
bash: mkvirtualenv: command not found
...
I had the same issue on OS X 10.9.1 with python 2.7.5. No issues with WORKON_HOME for me, but I did have to manually add source "/usr/local/bin/virtualenvwrapper.sh" to ~/.bash_profile (or ~/.bashrc in unix) after I ran pip install virtualenvwrapper
...