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String concatenation vs. string substitution in Python
... large boosts in performance..."
If performance matters, this is good to know.
However, performance problems I've seen have never come down to string operations. I've generally gotten in trouble with I/O, sorting and O(n2) operations being the bottlenecks.
Until string operations are the perfor...
Sending websocket ping/pong frame from browser
...was a recommended practice when user-agents were frequently refreshed. But now many websites are designed as SPAs. In this environment it might be quite essential for the client application to regularly ping the server in order to ensure the connection has not been lost.
– Noel...
Is there any async equivalent of Process.Start?
... immediately rather than waiting for the Process to actually exit. Do not know why, just a word of caution.
– Chris Moschini
Oct 1 '14 at 6:15
...
What's so wrong about using GC.Collect()?
...that respectable programmers wouldn't ever use, even those who don't even know what it is for.
20 Answers
...
Pass request headers in a jQuery AJAX GET call
...
i know this is super-old by now. but I wanted to add that there should be a comma after: beforeSend: function(xhr){xhr.setRequestHeader('X-Test-Header', 'test-value');}
– matthew_360
Jan ...
Replace specific characters within strings
..., "e18947")) )
R> group
group
1 12357e
2 12575e
3 197e18
4 e18947
Now use gsub() with the simplest possible replacement pattern: empty string:
R> group$groupNoE <- gsub("e", "", group$group)
R> group
group groupNoE
1 12357e 12357
2 12575e 12575
3 197e18 19718
4 e18947 ...
Why use bzero over memset?
...use you can achieve exactly the same functionality using memset function.
Now regarding efficiency, compilers like gcc use builtin implementations for memset which switch to a particular implementation when a constant 0 is detected. Same for glibc when builtins are disabled.
...
NumPy: function for simultaneous max() and min()
...tine minmax2
Compile it via:
f2py -m untitled -c fortran_code.f90
And now we're in a place where we can test it:
import timeit
size = 100000
repeat = 10000
print timeit.timeit(
'np.min(a); np.max(a)',
setup='import numpy as np; a = np.arange(%d, dtype=np.float32)' % size,
number=...
Determine which JAR file a class is from
I am not in front of an IDE right now, just looking at the API specs.
4 Answers
4
...
How do I get a UTC Timestamp in JavaScript?
...me is passed in, the results will differ. Observe (I'm in GMT +02:00 right now, and it's 07:50):
> var d1 = new Date();
> d1.toUTCString();
"Sun, 18 Mar 2012 05:50:34 GMT" // two hours less than my local time
> Math.floor(d1.getTime()/ 1000)
1332049834
> var d2 = new Date( d1.getUTCFu...