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get list from pandas dataframe column
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Pandas DataFrame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Seri...
Reshaping data.frame from wide to long format
...alues (as a result of the , in the numbers). You can repair that with gsub and as.numeric:
long$value <- as.numeric(gsub(",", "", long$value))
Or directly with data.table or dplyr:
# data.table
long <- melt(setDT(wide),
id.vars = c("Code","Country"),
variable.name...
How to automatically crop and center an image
... any arbitrary image, I want to crop a square from the center of the image and display it within a given square.
7 Answers
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Timer function to provide time in nano seconds using C++
...ed about running the function repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Li...
raw_input function in Python
... the user (the optional arg of raw_input([arg])), gets input from the user and returns the data input by the user in a string. See the docs for raw_input().
Example:
name = raw_input("What is your name? ")
print "Hello, %s." % name
This differs from input() in that the latter tries to interpret...
Accessing the web page's HTTP Headers in JavaScript
...o read the current headers. You could make another request to the same URL and read its headers, but there is no guarantee that the headers are exactly equal to the current.
Use the following JavaScript code to get all the HTTP headers by performing a get request:
var req = new XMLHttpRequest();...
URL encoding the space character: + or %20?
When is a space in a URL encoded to + , and when is it encoded to %20 ?
4 Answers
4
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PostgreSQL: Difference between text and varchar (character varying)
What's the difference between the text data type and the character varying ( varchar ) data types?
9 Answers
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What is the difference between “screen” and “only screen” in media queries?
What is the difference between screen and only screen in media queries?
5 Answers
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How to create an array containing 1…N
...is what you're looking for, why do you need an array? A simple var n = 45; and then looping from 1..n would do.
– casablanca
Sep 19 '10 at 18:33
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