大约有 11,000 项符合查询结果（耗时：0.0243秒） [XML]
Why doesn't print work in a lambda?
...
A lambda's body has to be a single expression. In Python 2.x, print is a statement. However, in Python 3, print is a function (and a function application is an expression, so it will work in a lambda). You can (and should, for forward compatibility :) use the back-ported pri...
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
In Python, the only way I can find to concatenate two lists is list.extend , which modifies the first list. Is there any concatenation function that returns its result without modifying its arguments?
...
How do I get the opposite (negation) of a Boolean in Python?
...ll __bool__ on the object.
So by implementing __bool__ (or __nonzero__ in Python 2) you can customize the truth value and thus the result of not:
class Test(object):
def __init__(self, value):
self._value = value
def __bool__(self):
print('__bool__ called on {!r}'.format(s...
How to move a model between two Django apps (Django 1.7)
... refer to my old answer.
First migration to remove model from 1st app.
$ python manage.py makemigrations old_app --empty
Edit migration file to include these operations.
class Migration(migrations.Migration):
database_operations = [migrations.AlterModelTable('TheModel', 'newapp_themodel')]...
Loop through all nested dictionary values?
...error:
RuntimeError: maximum recursion depth exceeded while calling a Python object
The same goes with the implementation from senderle.
Similarly, you get an infinite loop with this implementation from Fred Foo:
def myprint(d):
stack = list(d.items())
while stack:
...
Haversine Formula in Python (Bearing and Distance between two GPS points)
...
Here's a Python version:
from math import radians, cos, sin, asin, sqrt
def haversine(lon1, lat1, lon2, lat2):
"""
Calculate the great circle distance between two points
on the earth (specified in decimal degrees)
"...
How many system resources will be held for keeping 1,000,000 websocket open? [closed]
...at is the theoretical maximum number of open TCP connections that a modern Linux box can have
http://www.kegel.com/c10k.html
share
|
improve this answer
|
follow
...
Passing functions with arguments to another function in Python?
Is it possible to pass functions with arguments to another function in Python?
7 Answers
...
Double Iteration in List Comprehension
In Python you can have multiple iterators in a list comprehension, like
10 Answers
10
...
How to get the parents of a Python class?
How can I get the parent class(es) of a Python class?
6 Answers
6
...