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Why are there two kinds of functions in Elixir?
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edited Mar 27 '19 at 17:13
Paweł Obrok
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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 more efficient? Using pow to square or just multiply it with itself?
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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...
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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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 ...
How to reverse-i-search back and forth? [duplicate]
...ard shortcut twice.
– mklement0
Jan 27 '14 at 22:51
3
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JavaScript get clipboard data on paste event (Cross browser)
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327
Solution #1 (Plain Text only and requires Firefox 22+)
Works for IE6+, FF 22+, Chrome, Safari, ...
OwinStartup not firing
...e I was able to do so before. I tried to open an app in a browser, then in VS2013 to use "Debug-> Attach to Process", and then to reload a page in a browser. VS didn't stop. I know that OWIN Startup is executing: I put some logging into it for debug purposes. It's like back in a dark age of inter...