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Is there a way to make R beep/play a sound at the end of a script?
...ered Jul 1 '14 at 18:08
Rasmus BååthRasmus Bååth
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What is your preferred style for naming variables in R? [closed]
...ered Nov 16 '12 at 8:55
Rasmus BååthRasmus Bååth
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Add single element to array in numpy
...
for k in range(int(10e4)):
d.append(k)
f = np.array(d)
13.5 ms ± 277 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
Pre-allocating numpy array:
e = np.zeros((n,))
for k in range(n):
e[k] = k
9.92 ms ± 752 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
When the...
pypi UserWarning: Unknown distribution option: 'install_requires'
...ed Nov 28 '11 at 15:38
Fredrik HåårdFredrik Håård
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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...than raw column based filtration:-
%timeit df_new = df[(df.E>0)]
345 µs ± 10.5 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
%timeit dft.drop(dft[dft.E < 0].index, inplace=True)
890 µs ± 94.9 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
A column is basical...
Extract subset of key-value pairs from Python dictionary object?
...works in 2.7 too):
{k: bigdict[k] for k in ('l', 'm', 'n')}
Update: As Håvard S points out, I'm assuming that you know the keys are going to be in the dictionary - see his answer if you aren't able to make that assumption. Alternatively, as timbo points out in the comments, if you want a key tha...
Does PostgreSQL support “accent insensitive” collations?
... unaccent() always substitutes a single letter:
SELECT unaccent('Œ Æ œ æ ß');
unaccent
----------
E A e a S
You will love this update to unaccent in Postgres 9.6:
Extend contrib/unaccent's standard unaccent.rules file to handle all
diacritics known to Unicode, and expand ligatures cor...
Modifying a subset of rows in a pandas dataframe
...ings
%timeit df['b'] = np.where(df.a.values == 0, np.nan, df.b.values)
685 µs ± 6.4 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
%timeit df.loc[df['a'] == 0, 'b'] = np.nan
3.11 ms ± 17.2 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
Numpy's where is about 4x faster
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Check if something is (not) in a list in Python
... 0.613 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
178 µs ± 5.01 µs per loop (mean ± std. dev. of 7 runs, 10000 loops each)
If you want to do more than just check whether an item is in a list, there are options:
list.index can be used to retrieve the index of an item. If t...
.gitignore is ignored by Git
...red Mar 19 '14 at 23:40
H AßdøµH Aßdøµ
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