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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...
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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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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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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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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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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What is a coroutine?
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Coroutines and concurrency are largely orthogonal. Coroutines are a general control structure whereby flow control is cooperatively passed between two different routines without returning.
The 'yield' statement in Python is a good exam...
What is the difference between a database and a data warehouse?
What is the difference between a database and a data warehouse?
13 Answers
13
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Targeting both 32bit and 64bit with Visual Studio in same solution/project
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Yes, you can target both x86 and x64 with the same code base in the same project. In general, things will Just Work if you create the right solution configurations in VS.NET (although P/Invoke to entirely unmanaged DLLs will most likely require some cond...