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Sleep until a specific time/date
... correct number of seconds.
To do this in bash, do the following:
current_epoch=$(date +%s)
target_epoch=$(date -d '01/01/2010 12:00' +%s)
sleep_seconds=$(( $target_epoch - $current_epoch ))
sleep $sleep_seconds
To add precision down to nanoseconds (effectively more around milliseconds) use e....
Principal component analysis in Python
...is 2 x 20. Dropping the primes,
d . Vt 2 principal vars = p.vars_pc( 20 vars )
U 1000 obs = p.pc_obs( 2 principal vars )
U . d . Vt 1000 obs, p.obs( 20 vars ) = pc_obs( vars_pc( vars ))
fast approximate A . vars, using the `npc` principal components
Ut ...
Java 8: performance of Streams vs Collections
...me: 41856183 ns (0.041856 seconds)
Streams: Elapsed time: 546590322 ns (0.546590 seconds)
Parallel streams: Elapsed time: 1540051478 ns (1.540051 seconds)
That' s for a big task! (int max = 10000000) Conclusion: collecting items to collection took majority of time. The slowest part ...
What exactly are iterator, iterable, and iteration?
...and iterator have specific meanings.
An iterable is an object that has an __iter__ method which returns an iterator, or which defines a __getitem__ method that can take sequential indexes starting from zero (and raises an IndexError when the indexes are no longer valid). So an iterable is an object...
How to pip or easy_install tkinter on Windows
...'ll end up with a fresh install of ActivePython, located in, e.g. C:\python32. From a Windows command prompt, or the Start Menu's "Run..." command, you should then be able to run a Python shell via:
% C:\python32\python
This should give you the Python command prompt. From the prompt, enter these ...
Ternary Operator Similar To ?:
...
Rex KerrRex Kerr
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Can I get CONST's defined on a PHP class?
...
datashaman
4,47322 gold badges1919 silver badges2626 bronze badges
answered Jun 5 '09 at 15:15
Tom HaighTom Haigh
...
Scala best way of turning a Collection into a Map-by-key?
...Traversable[V].mapBy( V => K) were better!
– oxbow_lakes
Jul 14 '10 at 21:17
7
Be aware that t...
How to remove from a map while iterating it?
...begin(); it != m.cend() /* not hoisted */; /* no increment */)
{
if (must_delete)
{
m.erase(it++); // or "it = m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop sh...
Difference between passing array and array pointer into function in C
...t fix" bug report here connect.microsoft.com/VisualStudio/feedback/details/326874/…
– greggo
Dec 12 '13 at 17:02
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