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Convert to binary and keep leading zeros in Python
...n using format():
>>> import timeit
>>> timeit.timeit("f_(v, '#010b')", "v = 14; f_ = format") # use a local for performance
0.40298633499332936
>>> timeit.timeit("f'{v:#010b}'", "v = 14")
0.2850222919951193
But I'd use that only if performance in a tight loop matters,...
What are best practices that you use when writing Objective-C and Cocoa? [closed]
...ot think are standard:
1) With the advent of properties, I no longer use "_" to prefix "private" class variables. After all, if a variable can be accessed by other classes shouldn't there be a property for it? I always disliked the "_" prefix for making code uglier, and now I can leave it out.
2...
How to write an inline IF statement in JavaScript?
...developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Conditional_Operator
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How can the Euclidean distance be calculated with NumPy?
...er too much if you use sqrt-sum with axis=0, linalg.norm with axis=0, or
a_min_b = a - b
numpy.sqrt(numpy.einsum('ij,ij->j', a_min_b, a_min_b))
which is, by a slight margin, the fastest variant. (That actually holds true for just one row as well.)
The variants where you sum up over the second...
How to write a cron that will run a script every day at midnight?
...native.
# Run once after reboot.
@reboot /usr/local/sbin/run_only_once_after_reboot.sh
You can also use this trick to run your cron job multiple times per minute.
# Run every minute at 0, 20, and 40 second intervals
* * * * * sleep 00; /usr/local/sbin/run_3times_per_min...
How can I get the count of milliseconds since midnight for the current?
... // Get current moment in UTC, then…
.get( ChronoField.MILLI_OF_SECOND ) // interrogate a `TemporalField`.
2017-04-25T03:01:14.113Z → 113
Get the fractional second in nanoseconds (billions).
Divide by a thousand to truncate to milliseconds (thousands).
See this code run l...
Get MIME type from filename extension
...dd double checks and provide fail safe action for every step.
MimeMapping._mappingDictionary.AddMapping(string fileExtension, string mimeType)
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Can you create nested WITH clauses for Common Table Expressions?
...recursive query:
WITH y
AS
(
SELECT x, y, z
FROM MyTable
WHERE [base_condition]
UNION ALL
SELECT x, y, z
FROM MyTable M
INNER JOIN y ON M.[some_other_condition] = y.[some_other_condition]
)
SELECT *
FROM y
You may not need this functionality. I've done the following just to organ...
Easier way to create circle div than using an image?
... image is not circular..which is in mozilla.
– techie_28
Jan 6 '12 at 15:19
1
@techie_28: The div...
Invalid argument supplied for foreach()
...s to be the most clean - not sure if it's the most efficient, mind!
if (is_array($values) || is_object($values))
{
foreach ($values as $value)
{
...
}
}
The reason for my preference is it doesn't allocate an empty array when you've got nothing to begin with anyway.
...