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Numpy: find first index of value fast
...e(100000)
%timeit index(arr, 5) # 1000000 loops, best of 3: 1.88 µs per loop
%timeit find_first(5, arr) # 1000000 loops, best of 3: 1.7 µs per loop
%timeit index(arr, 99999) # 10000 loops, best of 3: 118 µs per loop
%timeit find_first(99999, arr) # 10000 loops, best of 3: 9...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...>> %timeit df3.groupby(df3.index).first()
1000 loops, best of 3: 580 µs per loop
>>> %timeit df3[~df3.index.duplicated(keep='first')]
1000 loops, best of 3: 307 µs per loop
Note that you can keep the last element by changing the keep argument to 'last'.
It should also be noted tha...
Approximate cost to access various caches and main memory?
... Mutex lock/unlock
100 ns Main memory (RAM)
2 000 ns (2µs) 1KB Zippy-compress
Still some improvements, prediction for 2020
16 000 ns (16µs) SSD random read (olibre's note: should be less)
500 000 ns (½ms) Round trip in datacenter
2 000 000 ns (2ms) HDD random read (s...
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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...
What's the difference between UTF-8 and UTF-8 without BOM?
...nded but it did wonders to my powershell script when trying to output "æøå"
– Marius
Nov 12 '13 at 9:22
63
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RE error: illegal byte sequence on Mac OS X
... :
iconv -f ISO-8859-1 -t UTF8-MAC file.txt | sed 's/something/àéèêçùû/g' | .....
-f option is the 'from' codeset and -t option is the 'to' codeset conversion.
Take care of case, web pages usually show lowercase like that < charset=iso-8859-1"/>
and iconv uses uppercase.
You hav...
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...