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Is there a simple, elegant way to define singletons? [duplicate]
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I don't really see the need, as a module with functions (and not a class) would serve well as a singleton. All its variables would be bound to the module, which could not be instantiated repeatedly anyway.
If you do wish to use a cla...
What is the documents directory (NSDocumentDirectory)?
...ath = paths.firstObject;
return basePath;
}
This Documents directory allows you to store files and subdirectories your app creates or may need.
To access files in the Library directory of your apps sandbox use (in place of paths above):
[NSSearchPathForDirectoriesInDomains(NSLibraryDirectory...
String concatenation vs. string substitution in Python
...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>&g...
Python read-only property
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Generally, Python programs should be written with the assumption that all users are consenting adults, and thus are responsible for using things correctly themselves. However, in the rare instance where it just does not make sens...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...maintain consistent color schemes across multiple data frames that are not all obtained by subsetting a single large data frame. Managing the factors levels in multiple data frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file.
One way...
Reverse colormap in matplotlib
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The standard colormaps also all have reversed versions. They have the same names with _r tacked on to the end. (Documentation here.)
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Get class that defined method
...ited Jun 20 '14 at 19:44
Aaron Hall♦
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answered Jun 7 '09 at 2:23
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sqlalchemy: how to join several tables by one query?
...rmissions.document,
).filter(
User.email == 'someemail',
).all()
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Fastest way to list all primes below N
...4.0 |
| sundaram3 | 416.0 |
+---------------------+-------+
Of all the methods tested, allowing numpy, for n=1000000,
primesfrom2to was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| primesfrom2to | 15.9 |
| p...
Design patterns or best practices for shell scripts [closed]
...first suggestion is "don't". The reason is that is fairly easy to make a small mistake that hinders your script, or even make it dangerous.
That said, I don't have other resources to pass you but my personal experience.
Here is what I normally do, which is overkill, but tends to be solid, although...