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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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Does disposing streamreader close the stream?
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Yes, StreamReader, StreamWriter, BinaryReader and BinaryWriter all close/dispose their underlying streams when you call Dispose on them. They don't dispose of the stream if the reader/writer is just garbage collected though - you should always dispose of the reader/writer, preferrably wi...
How to access data/data folder in Android device?
...'backup my data'. The resulting 'backup.ab' file on your computer contains all application data in android backup format. Basically it's a compressed tar file. This page explains how you can use OpenSSL's zlib command to uncompress it.
You can use the adb restore backup.db command to restore the b...
Backbone.View “el” confusion
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A views el is where all the event binding takes place. You don't have to use it but if you want backbone to fire events you need to do your rendering work on the el. A views el is a DOM element but it does not have to be a pre-existing element. ...
C++ Best way to get integer division and remainder
... experiment with g++ 6.3.0 on x86_64 revealed that with no optimization at all, you get two idivl instructions, but with -O1 or greater, you get one. As the manual says, “Without any optimization option … Statements are independent”.
– Tom Zych
Oct 15 '17...
Easy way to turn JavaScript array into comma-separated list?
...ers have indicated with an upvote) but more helpful might have been to actually provide the alternative answer with example code?
– Chris
Jul 8 '12 at 10:06
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How to get rid of punctuation using NLTK tokenizer?
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You do not really need NLTK to remove punctuation. You can remove it with simple python. For strings:
import string
s = '... some string with punctuation ...'
s = s.translate(None, string.punctuation)
Or for unicode:
import string
tra...
WARNING: UNPROTECTED PRIVATE KEY FILE! when trying to SSH into Amazon EC2 Instance
...SSH to interact with my own personal instance, but right now I'm not being allowed permission into Panda's EC2 instance.
Getting Started with Panda
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What is best tool to compare two SQL Server databases (schema and data)? [duplicate]
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The tool is really good - but as it was told earlier very expensive. I've choosen the alternative - dbForge Data Compare for SQL Server from Devart. The functionality is almost the same. It suits all my needs and is much cheaper.
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How do I use HTML as the view engine in Express?
...will work, but to serve out HTML, there is no need to use a view engine at all, unless you want to set up funky routing. Instead, just use the static middleware:
app.use(express.static(__dirname + '/public'));
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