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How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
...
Why is it slower to iterate over a small string than a small list?
...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
...
Get names of all keys in the collection
I'd like to get the names of all the keys in a MongoDB collection.
21 Answers
21
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What is the 'new' keyword in JavaScript?
...n's external, accessible, prototype object (every function object automatically has a prototype property).
It makes the this variable point to the newly created object.
It executes the constructor function, using the newly created object whenever this is mentioned.
It returns the newly created objec...
How to check if one DateTime is greater than the other in C#
...swered Sep 18 '08 at 19:17
Jon GallowayJon Galloway
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“ImportError: No module named” when trying to run Python script
...the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys.path list. In your notebook, fi...
How to do what head, tail, more, less, sed do in Powershell? [closed]
...an above option
gc log.txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.
The PowerShell Community Extensions include some cmdlets fo...
multiprocessing.Pool: When to use apply, apply_async or map?
...
Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is preferred. The...
How to write very long string that conforms with PEP8 and prevent E501
...
Implicit concatenation might be the cleanest solution:
s = "this is my really, really, really, really, really, really," \
" really long string that I'd like to shorten."
Edit On reflection I agree that Todd's suggestion to use brackets rather than line continuation is better for all the reas...
Algorithm to detect corners of paper sheet in photo
...n are awesome, move to them as soon as possible. :D
Instead of removing small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still stru...