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Specify custom Date format for colClasses argument in read.table/read.csv

... You can write your own function that accepts a string and converts it to a Date using the format you want, then use the setAs to set it as an as method. Then you can use your function as part of the colClasses. Try: setAs("character","myDate", function(from) as.Date(from, for...
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When do you need to explicitly call a superclass constructor?

...Well there's a difference between requiring the constructor to be present, and requiring an explicit delegation to the parameterless super-constructor. The latter is a matter of style - whether you prefer to be explicit/obvious or brief. – Jon Skeet Dec 11 '17 ...
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How to check if a table contains an element in Lua?

...r function is as efficient as can be done. Of course, as noted by others (and as practiced in languages older than Lua), the solution to your real problem is to change representation. When you have tables and you want sets, you turn tables into sets by using the set element as the key and true as ...
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Task not serializable: java.io.NotSerializableException when calling function outside closure only o

...sk to fail. Now this doesn't mean that you can serialise an RDD with Spark and avoid NotSerializableException Spark is a distributed computing engine and its main abstraction is a resilient distributed dataset (RDD), which can be viewed as a distributed collection. Basically, RDD's elements are par...
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How unique is UUID?

...ify something (I'm using it for files uploaded to the server)? As I understand it, it is based off random numbers. However, it seems to me that given enough time, it would eventually repeat it self, just by pure chance. Is there a better system or a pattern of some type to alleviate this issue? ...
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Check if array is empty or null

...hat you want. There are a lot of ways to clean up your code to be simpler and more readable. Here's a cleaned up version with notes about what I cleaned up. var album_text = []; $("input[name='album_text[]']").each(function() { var value = $(this).val(); if (value) { album_text.p...
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Remove duplicate rows in MySQL

... The aforementioned bug @DarkMantis referred to and it's solution. – Jordan Arseno Jan 23 '13 at 20:47 ...
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Make virtualenv inherit specific packages from your global site-packages

...ent with virtualenv --system-site-packages . Then, activate the virtualenv and when you want things installed in the virtualenv rather than the system python, use pip install --ignore-installed or pip install -I . That way pip will install what you've requested locally even though a system-wide vers...
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How can I obfuscate (protect) JavaScript? [closed]

I want to make a JavaScript application that's not open source, and thus I wish to learn how to can obfuscate my JS code? Is this possible? ...
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How do I uninstall a package installed using npm link?

... The package can be uninstalled using the same uninstall or rm command that can be used for removing installed packages. The only thing to keep in mind is that the link needs to be uninstalled globally - the --global flag needs to be provided. In order to uninstall the globally linked foo p...