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How to get the first word of a sentence in PHP?
...st($firstword) = explode(' ', trim($myvalue), 1);
– Cédric Françoys
Oct 27 '16 at 10:33
3
@Céd...
Print a string as hex bytes?
...
Verified,Python 3.7.6: import sys ; s="Déjà vu Besançon,Lupiñén,Šiauliai,Großräschen,Łódź,Аша,广东省,LA" ; for c in s: ; w=sys.stdout.write(c+":"+c.encode('utf-8').hex()+"||") ; (out) D:44||é:c3a9||j:6a||à:c3a0|| :20||v:76||u:75|| :20||B:42||e:65...
iPhone: How to get current milliseconds?
...if portability is a priority for you.
iPhone 4S
CACurrentMediaTime: 1.33 µs/call
gettimeofday: 1.38 µs/call
[NSDate timeIntervalSinceReferenceDate]: 1.45 µs/call
CFAbsoluteTimeGetCurrent: 1.48 µs/call
[[NSDate date] timeIntervalSince1970]: 4.93 µs/call
iPad 3
CACurrentMediaTime: 1.25 µs/c...
How to compare Unicode characters that “look alike”?
...ain(string[] args)
{
char first = 'μ';
char second = 'µ';
// Technically you only need to normalize U+00B5 to obtain U+03BC, but
// if you're unsure which character is which, you can safely normalize both
string firstNormalized = first.ToString().Normal...
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 add “active” class to Html.ActionLink in ASP.NET MVC
...as it groups them together in a logical manner.
– René Kåbis
Apr 28 '16 at 18:29
@René Kåbis it for bootstrap naig...
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...