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What's the fastest way to merge/join data.frames in R?
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The match approach works when there is a unique key in the second data frame for each key value in the first. If there are duplicates in the second data frame then the match and merge approaches are not the same. Match is, of course, faster since it is not doing as much. In ...
Relationship between hashCode and equals method in Java [duplicate]
I read in many places saying while override equals method in Java, should override hashCode method too, otherwise it is "violating the contract".
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How to make asynchronous HTTP requests in PHP
Is there a way in PHP to make asynchronous HTTP calls? I don't care about the response, I just want to do something like file_get_contents() , but not wait for the request to finish before executing the rest of my code. This would be super useful for setting off "events" of a sort in my application...
What are the file limits in Git (number and size)?
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This message from Linus himself can help you with some other limits
[...] CVS, ie it really ends up being pretty much oriented to a "one file
at a time" model.
Which is nice in that you can have a million files, and then only check
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Serving favicon.ico in ASP.NET MVC
What is the final/best recommendation for how to serve favicon.ico in ASP.NET MVC?
9 Answers
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Visual Studio Solutions Folder as real Folders
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No special setting. I don't think it's supported.
You can create real folders in a "project" within the solution, but not in the solution itself.
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Difference between single and double quotes in Bash
In Bash, what are the differences between single quotes ( '' ) and double quotes ( "" )?
6 Answers
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ES6 class variable alternatives
Currently in ES5 many of us are using the following pattern in frameworks to create classes and class variables, which is comfy:
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What does “=>” mean in PHP?
What does the => operator mean in the following code?
6 Answers
6
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Peak-finding algorithm for Python/SciPy
I can write something myself by finding zero-crossings of the first derivative or something, but it seems like a common-enough function to be included in standard libraries. Anyone know of one?
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