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Elegant way to check for missing packages and install them?
...de with coauthors these days. Many of them are novice/intermediate R users and don't realize that they have to install packages they don't already have.
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Can I use a :before or :after pseudo-element on an input field?
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:after and :before are not supported in Internet Explorer 7 and under, on any elements.
It's also not meant to be used on replaced elements such as form elements (inputs) and image elements.
In other words it's impossible with pur...
Correct Bash and shell script variable capitalization
I run across many shell scripts with variables in all caps, and I've always thought that there is a severe misunderstanding with that. My understanding is that, by convention (and perhaps by necessity long ago), environment variables are in all-caps.
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Comparison of Android networking libraries: OkHTTP, Retrofit, and Volley [closed]
Two-part question from an iOS developer learning Android, working on an Android project that will make a variety of requests from JSON to image to streaming download of audio and video:
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Preferred order of writing latitude & longitude tuples in GIS services
When dealing with GIS source code you often need to write latitude and longitude coordinate tuples.
9 Answers
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How do I calculate tables size in Oracle
Being used to (and potentially spoiled by) MSSQL, I'm wondering how I can get at tables size in Oracle 10g.
I have googled it so I'm now aware that I may not have as easy an option as sp_spaceused. Still the potential answers I got are most of the time outdated or don't work. Probably because I'm no...
How does Google calculate my location on a desktop?
... Maps, when clicked (without being logged into my Google Account) using standard Wi Fi to my own personal router and a normal internet connection to my ISP, it somehow manages to pinpoint my exact location with a 100% accuracy (at this moment in time).
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Extending an Object in Javascript
I am currently transforming from Java to Javascript, and it's a bit hard for me to figure out how to extend objects the way I want it to do.
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What is the difference between a database and a data warehouse?
What is the difference between a database and a data warehouse?
13 Answers
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What is the difference between class and instance methods?
What's the difference between a class method and an instance method?
18 Answers
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