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How to extract the n-th elements from a list of tuples?
...htly slower than the list comprehension:
setup = 'elements = [(1,1,1) for _ in range(100000)];from operator import itemgetter'
method1 = '[x[1] for x in elements]'
method2 = 'map(itemgetter(1), elements)'
import timeit
t = timeit.Timer(method1, setup)
print('Method 1: ' + str(t.timeit(100)))
t = t...
Scala: write string to file in one statement
....write(Paths.get("file.txt"), "file contents".getBytes(StandardCharsets.UTF_8))
I think this is by far the simplest and easiest and most idiomatic way, and it does not need any dependencies sans Java itself.
share
...
What is a regular expression for a MAC Address?
...perty \p{xdigit} includes the FULLWIDTH versions. You might prefer \p{ASCII_Hex_Digit} instead.
The answer to the question asked might be best answered — provided you have a certain venerable CPAN module installed — by typing:
% perl -MRegexp::Common -lE 'say $RE{net}{MAC}'
I show the partic...
ValueError: setting an array element with a sequence
...9 when building an array of objects (not necessarily lists) that implement __getitem__ as specified here:github.com/numpy/numpy/issues/5100
– dashesy
Nov 21 '14 at 19:13
add a...
Why should text files end with a newline?
...ter.
Source: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206
An incomplete line as:
A sequence of one or more non- <newline> characters at the end of the file.
Source: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_1...
How to elegantly ignore some return values of a MATLAB function?
...
I personally just use [junk, junk, c] = function_call() and assume both that "junk" is never an important variable and if it contains a lot of memory that I will clear it if necessary.
– Jason S
Apr 14 '09 at 13:13
...
Node.js vs .Net performance
...:
Dell Latitude E6510, Core i5 (dual core), 8 GB RAM, Windows 7 Enterprise 64 bit OS
node server
runs at http://localhost:9090/
/// <reference path="node-vsdoc.js" />
var http = require("http");
http.createServer(function (request, response) {
response.writeHead(200, { "Content-Type": "text/...
Splitting templated C++ classes into .hpp/.cpp files--is it possible?
...
You can do it in this way
// xyz.h
#ifndef _XYZ_
#define _XYZ_
template <typename XYZTYPE>
class XYZ {
//Class members declaration
};
#include "xyz.cpp"
#endif
//xyz.cpp
#ifdef _XYZ_
//Class definition goes here
#endif
This has been discussed in Daniweb
...
What characters are valid for JavaScript variable names?
...mmarizing the relevant spec sections:
An identifier must start with $, _, or any character in the Unicode categories “Uppercase letter (Lu)”, “Lowercase letter (Ll)”, “Titlecase letter (Lt)”, “Modifier letter (Lm)”, “Other letter (Lo)”, or “Letter number (Nl)”.
The r...
Is it possible to clone html element objects in JavaScript / JQuery?
...ipt using the cloneNode() method:
// Create a clone of element with id ddl_1:
let clone = document.querySelector('#ddl_1').cloneNode( true );
// Change the id attribute of the newly created element:
clone.setAttribute( 'id', newId );
// Append the newly created element on element p
document.quer...
