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val-mutable versus var-immutable in Scala
...concurrency. And while we're at it, note the preferred use of synchronised vs @volatile vs something like AtomicReference: three tools
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What is more efficient? Using pow to square or just multiply it with itself?
...
I tested the performance difference between x*x*... vs pow(x,i) for small i using this code:
#include <cstdlib>
#include <cmath>
#include <boost/date_time/posix_time/posix_time.hpp>
inline boost::posix_time::ptime now()
{
return boost::posix_time::micro...
Drop data frame columns by name
...cars
colnames(dat)
# [1] "mpg" "cyl" "disp" "hp" "drat" "wt" "qsec" "vs" "am" "gear"
# [11] "carb"
dat[,c("mpg","cyl","wt")] <- list(NULL)
colnames(dat)
# [1] "disp" "hp" "drat" "qsec" "vs" "am" "gear" "carb"
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What is the most efficient way to concatenate N arrays?
...s is very slow for arrays containing objects, see: jsperf.com/array-concat-vs-array-push-vs-array-spread/1
– hitautodestruct
Jun 11 at 6:06
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Detect IE version (prior to v9) in JavaScript
...ning in IE7 standards mode? msdn.microsoft.com/en-us/library/ie/cc196988(v=vs.85).aspx
– mason81
Nov 19 '13 at 22:35
4
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Get a list of all threads currently running in Java
...ernatives, but I've worked with other Java means of gathering stack traces vs just a list of threads. The performance impact seems to depend very strongly on which JVM you are using (JRockit vs Sun JVM for example). It's worth measuring in your specific instance. Whether or not it will affect you...
Resetting generator object in Python
... too many values, that can be unpractical.
So you have the classic memory vs. processing tradeoff. I can't imagine a way of rewinding the generator without either storing the values or calculating them again.
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UnicodeDecodeError when reading CSV file in Pandas with Python
...python')
Alternate Solution:
Open the csv file in Sublime text editor or VS Code.
Save the file in utf-8 format.
In sublime, Click File -> Save with encoding -> UTF-8
Then, you can read your file as usual:
import pandas as pd
data = pd.read_csv('file_name.csv', encoding='utf-8')
and the ...
.append(), prepend(), .after() and .before()
... answered Dec 21 '14 at 12:57
VSri58VSri58
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What's the difference between a file descriptor and file pointer?
...ely available to Windows, e.g. msdn.microsoft.com/en-us/library/z0kc8e3z%28VS.80%29.aspx
– kennytm
Mar 11 '10 at 9:16
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