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Single quotes vs. double quotes in C or C++
When should I use single quotes and double quotes in C or C++ programming?
12 Answers
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subtle differences between JavaScript and Lua [closed]
...= operators are of lower precedence than >, >=, <, <=. In Lua, all comparison operators are the same precedence.
Lua supports tail calls.
UPDATE: JS now supports tail calls.
Lua supports assignment to a list of variables. While it isn't yet standard in Javascript, Mozilla's JS engine ...
Pip freeze vs. pip list
...you are using a virtualenv, you can specify a requirements.txt file to install all the dependencies.
A typical usage:
$ pip install -r requirements.txt
The packages need to be in a specific format for pip to understand, which is
feedparser==5.1.3
wsgiref==0.1.2
django==1.4.2
...
That is the ...
Unable to find specific subclass of NSManagedObject
...://stackoverflow.com/a/31287260/1187415).
Remark: This answer was originally written for Xcode 6.
There were some changes in the various Xcode 7 beta releases with
respect to this problem. Since it is an accepted answer with many
upvotes and links to it, I have tried to summarize the situation
fo...
How to import multiple .csv files at once?
...ariables but each from different times.
Is there a way in R to import them all simultaneously rather than having to import them all individually?
...
What are the main performance differences between varchar and nvarchar SQL Server data types?
I'm working on a database for a small web app at my school using SQL Server 2005 .
I see a couple of schools of thought on the issue of varchar vs nvarchar :
...
Difference between __str__ and __repr__?
...e come right out and say it — I do not believe in debuggers. I don’t really know how to use any debugger, and have never used one seriously. Furthermore, I believe that the big fault in debuggers is their basic nature — most failures I debug happened a long long time ago, in a galaxy far far a...
ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
How do I set the figure title and axes labels font size in Matplotlib?
...ze=18)
plt.ylabel('ylabel', fontsize=16)
fig.savefig('test.jpg')
For globally setting title and label sizes, mpl.rcParams contains axes.titlesize and axes.labelsize. (From the page):
axes.titlesize : large # fontsize of the axes title
axes.labelsize : medium # fontsize of the x any y...
How to make good reproducible pandas examples
...s.
Disclaimer: Writing a good question is HARD.
The Good:
do include small* example DataFrame, either as runnable code:
In [1]: df = pd.DataFrame([[1, 2], [1, 3], [4, 6]], columns=['A', 'B'])
or make it "copy and pasteable" using pd.read_clipboard(sep='\s\s+'), you can format the text for Sta...