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How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
Segue to another storyboard?
...;
// Load the initial view controller from the storyboard.
// Set this by selecting 'Is Initial View Controller' on the appropriate view controller in the storyboard.
UIViewController *theInitialViewController = [secondStoryBoard instantiateInitialViewController];
//
// **OR**
//
// Load the view...
Constant Amortized Time
...erations". Amortised time doesn't have to be constant; you can have linear and logarithmic amortised time or whatever else.
Let's take mats' example of a dynamic array, to which you repeatedly add new items. Normally adding an item takes constant time (that is, O(1)). But each time the array is ful...
RegEx: Grabbing values between quotation marks
... Please, why this works? I was using src="(.*)" but obviously it was selecting everything before the last ", your REGEX, though, selected only the src="" contents, but I didn't understand how?
– Lucas Bustamante
Jul 25 '18 at 23:25
...
Is it possible to download an old APK for my app from Google Play?
... releases => Production (Manage Production) => Release history => Select the version that you want => Click on Download button.
Your account should be granted with full permissions, otherwise the download button will be hidden.
Original Answer
Go to
Developer Console => Ma...
Bash history without line numbers
...ply vertical whitespace or indenting at paragraph breaks, depending on the selected style."
$ history | awk ' $1=""; {print}'
clear
echo "In word processing and desktop publishing, a hard return or paragraph break indicates a new paragraph, to be distinguished from the soft return at the end of a...
URLs: Dash vs. Underscore [closed]
...
also worth noting that underscored_text is selectable as a whole by double clicking in some devices and long-pressing on mobiles, whereas with dash-separated-text the same actions select each separated word. Think about if a user would ever try to copy out something f...
Regular expression to match balanced parentheses
I need a regular expression to select all the text between two outer brackets.
21 Answers
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What is the difference between a schema and a table and a database?
...chema (tables he/she owns) however user can also see any schemas they have select priviliedges on. So a database can consist of hundreds of schemas, and each schema hundreds of tables. You can have tables with the same name in different schemas, which are in the same database.
A Table is a table, ...
Are there console commands to look at whats in the queue and to clear the queue in Sidekiq?
...ou could do all of this even more easily via redis-cli :
$ redis-cli
> select 0 # (or whichever namespace Sidekiq is using)
> keys * # (just to get an idea of what you're working with)
> smembers queues
> lrange queues:app_queue 0 -1
> lrem queues:app_queue -1 "payload"
...