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Are Swift variables atomic?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
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a __getitem__ method that can take sequential indexes starting from zero (and raises an IndexError when the indexes are no longer valid).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...
Ternary Operator Similar To ?:
...
Rex KerrRex Kerr
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...
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 ...
Can I get CONST's defined on a PHP class?
...
datashaman
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answered Jun 5 '09 at 15:15
Tom HaighTom Haigh
...
How do I read the contents of a Node.js stream into a string variable?
...INVALID_ARG_TYPE]: The "list[0]" argument must be an instance of Buffer or Uint8Array. Received type string if the stream produces string chunks instead of Buffer. Using chunks.push(Buffer.from(chunk)) should work with both string and Buffer chunks.
– Andrei LED
...
How is Math.Pow() implemented in .NET Framework?
...rsion from Henry Warren's Hacker's Delight:
public static int iexp(int a, uint b) {
int y = 1;
while(true) {
if ((b & 1) != 0) y = a*y;
b = b >> 1;
if (b == 0) return y;
a *= a;
}
}
He notes that this operation is optimal (does the minimu...