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Finding a substring within a list in Python [duplicate]
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sub = 'abc'
timeit.timeit('[s for s in mylist if sub in s]', setup='from __main__ import mylist, sub', number=100000)
# for me 7.949463844299316 with Python 2.7, 8.568840944994008 with Python 3.4
timeit.timeit('next((s for s in mylist if sub in s), None)', setup='from __main__ import mylist, sub',...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...
Writing string to a file on a new line every time
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You can use:
file.write(your_string + '\n')
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Best practices for adding .gitignore file for Python projects? [closed]
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You should probably put the *.svn in your .global_gitignore, not in individual projects.
– cowlicks
Jan 15 '16 at 20:56
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How to reshape data from long to wide format
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@indra_patil - I would likely use the reshape2 package as indicated in one of the other answers. You could create a new question that's specific to your use case and post it if you can't figure it out.
– Chase...
How can I check if a Perl array contains a particular value?
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Simply turn the array into a hash:
my %params = map { $_ => 1 } @badparams;
if(exists($params{$someparam})) { ... }
You can also add more (unique) params to the list:
$params{$newparam} = 1;
And later get a list of (unique) params back:
@badparams = keys %params;
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What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...e
### HEADER ###
LOCKFILE="/var/lock/`basename $0`"
LOCKFD=99
# PRIVATE
_lock() { flock -$1 $LOCKFD; }
_no_more_locking() { _lock u; _lock xn && rm -f $LOCKFILE; }
_prepare_locking() { eval "exec $LOCKFD>\"$LOCKFILE\""; trap _no_more_locking EXIT; }
# ON START
_prepare_l...
Convert a row of a data frame to vector
...u have to be careful if your row contains a factor. Here is an example:
df_1 = data.frame(V1 = factor(11:15),
V2 = 21:25)
df_1[1,] %>% as.numeric() # you expect 11 21 but it returns
[1] 1 21
Here is another example (by default data.frame() converts characters to factors)
d...
How should I structure a Python package that contains Cython code
...od relies on the fact that building a .pyx file with Cython.Distutils.build_ext (at least with Cython version 0.14) always seems to create a .c file in the same directory as the source .pyx file.
Here is a cut-down version of setup.py which I hope shows the essentials:
from distutils.core import s...
How do I do an OR filter in a Django query?
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@alexis: you could also do Item.objects.filter(creator__in=creators), for example.
– Kevin London
Dec 9 '14 at 23:11
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