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Best practice for Python assert
...essThanZeroException(Exception):
pass
class variable(object):
def __init__(self, value=0):
self.__x = value
def __set__(self, obj, value):
if value < 0:
raise LessThanZeroException('x is less than zero')
self.__x = value
def __get__(self, o...
How to remove the querystring and get only the url?
...u can use strtok to get string before first occurence of ?
$url = strtok($_SERVER["REQUEST_URI"], '?');
strtok() represents the most concise technique to directly extract the substring before the ? in the querystring. explode() is less direct because it must produce a potentially two-element arr...
How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
How do I get an animated gif to work in WPF?
...e gif has 10 frames per second.
class GifImage : Image
{
private bool _isInitialized;
private GifBitmapDecoder _gifDecoder;
private Int32Animation _animation;
public int FrameIndex
{
get { return (int)GetValue(FrameIndexProperty); }
set { SetValue(FrameIndexProp...
Why use String.Format? [duplicate]
...ing s = string.Format("Hey, {0} it is the {1}st day of {2}. I feel {3}!", _name, _day, _month, _feeling);
vs:
string s = "Hey," + _name + " it is the " + _day + "st day of " + _month + ". I feel " + feeling + "!";
Format Specifiers
(and this includes the fact you can write custom formatters)
...
fork() branches more than expected?
...
when i=0
Process_1: Buffered text= 1 dot
Process_2(created by Process_1): Buffered text= 1 dot
when i=1
Process_3(created by Process_1): Inherit 1 buffered dot from Process_1 and prints 1 dot by itself. In total Process_3 prints 2 dots.
...
How to import multiple .csv files at once?
...olutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:lengt...
Reimport a module in python while interactive
...from the importlib library instead:
import importlib
importlib.reload(some_module)
If you are using python 3.2 or 3.3 you should:
import imp
imp.reload(module)
instead. See http://docs.python.org/3.0/library/imp.html#imp.reload
If you are using ipython, definitely consider using the autor...
Getting the docstring from a function
...
Interactively, you can display it with
help(my_func)
Or from code you can retrieve it with
my_func.__doc__
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Is cout synchronized/thread-safe?
... @ildjarn - No, @edA-qa mort-ora-y is correct. As long as cout.sync_with_stdio() is true, using cout to output characters from multiple threads without additional synchronization is well-defined, but only on the level of individual bytes. Thus, cout << "ab"; and cout << "cd" exec...