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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...
What is the difference between encode/decode?
...n as encoding. Use u'...'.encode(encoding).
Example:
>>> u'æøå'.encode('utf8')
'\xc3\x83\xc2\xa6\xc3\x83\xc2\xb8\xc3\x83\xc2\xa5'
>>> u'æøå'.encode('latin1')
'\xc3\xa6\xc3\xb8\xc3\xa5'
>>> u'æøå'.encode('ascii')
UnicodeEncodeError: 'asci...
What is the equivalent of the C++ Pair in Java?
...return "(" + first + ", " + second + ")";
– Juha Syrjälä
Sep 1 '09 at 8:31
6
Also, either mark ...
Multi-project test dependencies with gradle
...s no longer a public property of a project.
– David Pärsson
Jan 14 '13 at 10:39
3
...
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...
Split a string by a delimiter in python
...he variable ev contains this string and we apply separator '@':
Sa., 23. März@19:00@Klavier + Orchester: SPEZIAL
Then, after split operation the variable
date will have value "Sa., 23. März"
time will have value "19:00"
event_name will have value "Klavier + Orchester: SPEZIAL"
...
Hashing a string with Sha256
... answered May 18 at 19:26
Erçin DedeoğluErçin Dedeoğlu
3,22944 gold badges3434 silver badges5656 bronze badges
...
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...
How do you get a timestamp in JavaScript?
...ow it will look:
new Date()
Thu Oct 29 2015 08:46:30 GMT+0100 (Mitteleuropäische Zeit )
new Date(now())
Thu Oct 29 1970 09:46:30 GMT+0100 (Mitteleuropäische Zeit )
Of course it will break daylight saving time but depending on what you
are building this might be useful to you if you need t...
CSS Font Border?
...hird argument in order to have no blur at all.
– François Feugeas
Jun 21 '11 at 15:02
add a ...