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Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...
What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
...
Where IN clause in LINQ [duplicate]
... source, params T[] list)
{
return list.Contains(source);
}
Now you call:
var states = _objdatasources.StateList().Where(s => s.In(countrycodes));
You can pass individual values too:
var states = tooManyStates.Where(s => s.In("x", "y", "z"));
Feels more natural and closer to sql.
...
Python multiprocessing PicklingError: Can't pickle
...the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/lib/p...
How to plot two columns of a pandas data frame using points?
...
You can specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(...
Which is faster in Python: x**.5 or math.sqrt(x)?
...
I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
13
...
Can modules have properties the same way that objects can?
...s? When I put this code in one file x.py and import it from another, then calling x.y results in AttributeError: 'NoneType' object has no attribute 'c', since _M somehow has value None...
– Stephan202
May 19 '09 at 1:35
...
How do I check for C++11 support?
...t have (partial) compiler-level support versus a standard C++ library with all the C++11 changes.
So Boost's defines mentioned in another answer remain the only sane way to figure out if there is, for example, support for C++11 threads and other specific parts of the standard.
...
Quickest way to convert a base 10 number to any base in .NET?
...comments, Convert.ToString only supports the following limited - but typically sufficient - set of bases: 2, 8, 10, or 16.
Update (to meet the requirement to convert to any base):
I'm not aware of any method in the BCL which is capable to convert numbers to any base so you would have to write you...
Left Align Cells in UICollectionView
...ep their size, add the following at the top of the closure in the forEach call:
guard layoutAttribute.representedElementCategory == .cell else {
return
}
Objective-C:
- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect {
NSArray *attributes = [super layoutAttributesForElementsI...