大约有 3,000 项符合查询结果（耗时：0.0117秒） [XML]
Insert an element at a specific index in a list and return the updated list
...ents for Python 3.4.5:
Mine answer using sliced insertion - Fastest (3.08 µsec per loop)
mquadri$ python3 -m timeit -s "a = list(range(1000))" "b = a[:]; b[500:500] = [3]"
100000 loops, best of 3: 3.08 µsec per loop
ATOzTOA's accepted answer based on merge of sliced lists - Second (6.71 µsec...
“Cloning” row or column vectors
...t;>> %timeit np.array(np.broadcast_to(x, (reps, n)))
10.2 ms ± 62.3 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
>>> %timeit np.repeat(x[np.newaxis, :], reps, axis=0)
9.88 ms ± 52.4 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
>>> %timeit np.ti...
Python dictionary: Get list of values for list of keys
...imeit map(lambda _: m[_], l) # using 'map'
1000000 loops, best of 3: 1.66 µs per loop
In[5]: %timeit list(m[_] for _ in l) # a generator expression passed to a list constructor.
1000000 loops, best of 3: 1.65 µs per loop
In[6]: %timeit map(m.__getitem__, l)
The slowest run took 4.01 times longer...
Return multiple columns from pandas apply()
...best of 3: 2.61 ms per loop
Return tuple:
1000 loops, best of 3: 819 µs per loop
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How to get method parameter names?
...ct 20 '08 at 14:24
Jouni K. SeppänenJouni K. Seppänen
33.9k55 gold badges6767 silver badges9696 bronze badges
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How to select rows from a DataFrame based on column values?
...imeit mask = df['A'].values == 'foo'
%timeit mask = df['A'] == 'foo'
5.84 µs ± 195 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)
166 µs ± 4.45 µs per loop (mean ± std. dev. of 7 runs, 10000 loops each)
Evaluating the mask with the numpy array is ~ 30 times faster. This is pa...
How to calculate moving average using NumPy?
...an ± std. dev. of 7 runs, 1 loop each)
scipy.convolve :
1.07 ms ± 26.7 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
scipy.convolve, edge handling :
4.68 ms ± 9.69 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
numpy.cumsum :
5.31 ms ± 5.11 µs per loop (mean ± s...
String comparison: InvariantCultureIgnoreCase vs OrdinalIgnoreCase? [duplicate]
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how does InvariantCultureIgnoreCase behave when he meet ä ? as oppose to OrdinalIgnoreCase ...?
– Royi Namir
Nov 8 '12 at 14:28
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Set value for particular cell in pandas DataFrame using index
...
In [18]: %timeit df.set_value('C', 'x', 10)
100000 loops, best of 3: 2.9 µs per loop
In [20]: %timeit df['x']['C'] = 10
100000 loops, best of 3: 6.31 µs per loop
In [81]: %timeit df.at['C', 'x'] = 10
100000 loops, best of 3: 9.2 µs per loop
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What does the “expand” option do in grunt-contrib-copy? The examples all use it but the docs say not
...r is not correct. It is at best simplified.
– David Pärsson
Mar 6 '15 at 14:03
3
-1. This is mis...