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How to use filter, map, and reduce in Python 3
... longer return lists:
[...]
map() and filter() return iterators. If you really need a list, a quick fix is e.g. list(map(...)), but a better fix is often to use a list comprehension (especially when the original code uses lambda), or rewriting the code so it doesn’t need a list at all. Particular...
Rename all files in directory from $filename_h to $filename_half?
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Just use bash, no need to call external commands.
for file in *_h.png
do
mv "$file" "${file/_h.png/_half.png}"
done
Do not add #!/bin/sh
For those that need that one-liner:
for file in *.png; do mv "$file" "${file/_h.png/_half.png}"; done
...
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...
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...
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...
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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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...
sqlalchemy: how to join several tables by one query?
...rmissions.document,
).filter(
User.email == 'someemail',
).all()
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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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