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How to step through Python code to help debug issues?
...rSummoner, pudb is great for that. Also pydev
– alpha_989
Jun 11 '18 at 19:45
pdb is not a command line tool. To use i...
How to print a percentage value in python?
...If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The above 33% example would could now be written without the explicit
# float conversion:
>>> print "{0:.0f}%".format...
Creating a blocking Queue in .NET?
...ublic class BlockingQueue<T>
{
private readonly Subject<T> _queue;
private readonly IEnumerator<T> _enumerator;
private readonly object _sync = new object();
public BlockingQueue()
{
_queue = new Subject<T>();
_enumerator = _queue.GetEnume...
Django 1.7 - makemigrations not detecting changes
... out) listed in the documentation:
python manage.py makemigrations your_app_label
The documentation does not make it obvious that you need to add the app label to the command, as the first thing it tells you to do is python manage.py makemigrations which will fail. The initial migration is don...
Which SQL query is faster? Filter on Join criteria or Where clause?
...
# explain analyze select e.* from event e join result r on e.id = r.event_id and r.team_2_score=24;
QUERY PLAN
-------------------------------------------------------------------------------------...
Can I zip more than two lists together in Scala?
...neLists[A](ss:List[A]*) = {
val sa = ss.reverse;
(sa.head.map(List(_)) /: sa.tail)(_.zip(_).map(p=>p._2 :: p._1))
}
For example:
combineLists(List(1, 2, 3), List(10,20), List(100, 200, 300))
// => List[List[Int]] = List(List(1, 10, 100), List(2, 20, 200))
The answer is truncated t...
Allowed characters in Linux environment variable names
...EE Std
1003.1-2001 consist solely of uppercase letters, digits, and the '_'
(underscore) from the characters
defined in Portable Character Set and
do not begin with a digit. Other
characters may be permitted by an
implementation; applications shall
tolerate the presence of such names.
...
Can someone explain __all__ in Python?
I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files. Can someone explain what this does?
...
What is the common header format of Python files?
...d you will not have access to it in interactive sessions (i.e. through obj.__doc__) or when generating documentation with automated tools.
Import built-in modules first, followed by third-party modules, followed by any changes to the path and your own modules. Especially, additions to the path and n...
Two way/reverse map [duplicate]
...ic that you want. Here's a basic example:
class TwoWayDict(dict):
def __setitem__(self, key, value):
# Remove any previous connections with these values
if key in self:
del self[key]
if value in self:
del self[value]
dict.__setitem__(self,...