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Get Unix Epoch Time in Swift
...alSince1970)
let preciseMilliseconds = Int(Date().timeIntervalSince1970 * 1_000)
let preciseMicroseconds = Int(Date().timeIntervalSince1970 * 1_000_000) // most likely precise
Unfortunately, however, in the year 2038, 32-bit numbers won't be usable for the Unix timestamp and they'll have to be 64-...
Renaming columns in pandas
...UMNS
Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:
df = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})
# Or rename the existing DataFrame (rather than creating a copy)
df.rename(columns={'oldName1': 'newName1', 'oldNam...
Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2]...
C# properties: how to use custom set property without private field?
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What's the difference between this and not having set at all?
– Sidhin S Thomas
Nov 11 '19 at 16:59
3
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Is C++14 adding new keywords to C++?
...last change to the keywords table took place back in August 2011 (it's actually the first commit: that table hasn't changed since the repo went live around the time C++11 was being finalised).
Alternatively we can ask GitHub to compare the two drafts that were sent for ballot for both versions of ...
How do I globally configure RSpec to keep the '--color' and '--format specdoc' options turned on
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One can also use a spec_helper.rb file in all projects. The file should include the following:
RSpec.configure do |config|
# Use color in STDOUT
config.color = true
# Use color not only in STDOUT but also in pagers and files
config.tty = true
# Use the s...
MySQL get the date n days ago as a timestamp
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DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT U...
Get name of current class?
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obj.__class__.__name__ will get you any objects name, so you can do this:
class Clazz():
def getName(self):
return self.__class__.__name__
Usage:
>>> c = Clazz()
>>> c.getName()
'Clazz'
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List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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Java: PrintStream to String?
...that object. How can I capture this function's output in a String? Specifically, I want to use it as in a toString method.
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