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How to delete a row by reference in data.table?
...k.
delete <- function(DT, del.idxs) { # pls note 'del.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
...
Entity Framework - Invalid Column Name '*_ID"
...Studio Debug to EF DatabaseContext.Database.Log to output generated SQL to VS Output->Debug window
db.Database.Log = s => System.Diagnostics.Debug.WriteLine(s);
And generated SQL had 2 relations from B table -> one with correct id and other with the A_Id
The issue for the problem was, t...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...w I see how my question was indeed misguided regarding function invocation vs function definition.
– Rob Bednark
Sep 30 '12 at 15:54
25
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How/When does Execute Shell mark a build as failure in Jenkins?
... answered Apr 2 '14 at 15:23
SlavSlav
24.3k99 gold badges6767 silver badges9292 bronze badges
...
Check if a string matches a regex in Bash script
...a. By the way, be very careful with localized date format (Month-Day-Year vs. Day-Month-Year for instance)
– Django Janny
Mar 27 '18 at 18:35
...
Simplest/Cleanest way to implement singleton in JavaScript?
...g/0103_static_considered_harmful.html - phparch.com/2010/03/static-methods-vs-singletons-choose-neither
– Benjamin Gruenbaum
Nov 17 '13 at 19:35
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What is the python “with” statement designed for?
...or row in lines:
with open("outfile","a") as f:
f.write(row)
vs
with open("outfile","a") as f:
for row in lines:
f.write(row)
The first way is opening and closing the file for each row which may cause performance problems compared to the second way with opens and closes ...
When to throw an exception?
...
community wiki
2 revsThe Digital Gabeg
18
...
C# How can I check if a URL exists/is valid?
...DownloadString to check for errors; no error? It exists...
With C# 2.0 (VS2005):
private bool headOnly;
public bool HeadOnly {
get {return headOnly;}
set {headOnly = value;}
}
and
using(WebClient client = new MyClient())
{
// code as before
}
...
Is it possible to pass a flag to Gulp to have it run tasks in different ways?
...bine it with gulp-if to conditionally pipe the stream, very useful for dev vs. prod building:
var argv = require('yargs').argv,
gulpif = require('gulp-if'),
rename = require('gulp-rename'),
uglify = require('gulp-uglify');
gulp.task('my-js-task', function() {
gulp.src('src/**/*.js')
...