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What does .SD stand for in data.table in R
...history of baseball
fkt = c('teamIDBR', 'teamIDlahman45', 'teamIDretro')
# confirm that they're stored as `character`
Teams[ , sapply(.SD, is.character), .SDcols = fkt]
# teamIDBR teamIDlahman45 teamIDretro
# TRUE TRUE TRUE
If you're confused by the use of sapply here,...
How to exit from Python without traceback?
...est printing in stderr sys.stderr.write(msg)
– vinilios
Jan 17 '12 at 17:20
14
I strongly suggest...
What are the functional differences between NW.js, Brackets-Shell and Electron?
...s stand-alone desktop applications. The three viable options I have run across so far, are NW.js (formerly node-webkit), brackets-shell , and Electron (formerly atom-shell).
...
Single Page Application: advantages and disadvantages [closed]
...ke time to first byte, time to build DOM, network round trip for the HTML, onload event, etc. Updating the page post-load via AJAX would not be measured. There are solutions which let you instrument your code to record explicit measures, like when clicking a link, start a timer, then end a timer a...
Add Keypair to existing EC2 instance
...nd modify security settings
Choose your EC2 key pair and click Apply
Click confirm to confirm the update. It will terminate the environment and apply the key value to your environment.
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What is the maximum amount of RAM an app can use?
... brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 4...
How to send a stacktrace to log4j?
... The logger takes an object for its first argument and will toString() it. However the second argument has to be a Throwable and displays the stack trace.
– Peter Lawrey
Dec 3 '10 at 16:50
...
What makes a keychain item unique (in iOS)?
... brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 4...
Print a file's last modified date in Bash
...
Note that on OS X (Mac), it's stat -f "%m%t%Sm %N" filename (see man stat examples for more details)
– Olie
Oct 9 '14 at 23:45
...
How to determine programmatically whether a particular process is 32-bit or 64-bit
...{
using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Runtime.InteropServices;
internal static class Program
{
private static void Main()
{
foreach (var p in Process.GetProcesses())
{
try
...