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Set environment variables on Mac OS X Lion

...ble you set in your .bash_profile will only affect your bash shells. Generally I only set variables in my .bash_profile file and don't change the .plist file (or launchd file on Mavericks). Most OS X windowed applications don't need any custom environment. Only when an application actually needs a ...
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Counting inversions in an array

...m to do the following: Given array A[1... n] , for every i < j , find all inversion pairs such that A[i] > A[j] . I'm using merge sort and copying array A to array B and then comparing the two arrays, but I'm having a difficult time seeing how I can use this to find the number of inversions...
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How do I get a UTC Timestamp in JavaScript?

While writing a web application, it makes sense to store (server side) all datetimes in the DB as UTC timestamps. 16 Answ...
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Can you create nested WITH clauses for Common Table Expressions?

... Essentially the post means, that you can't do it, but it is not a big problem. – peterh - Reinstate Monica May 30 '17 at 14:40 ...
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What are “first class” objects?

...as any other object. A first class object is an entity that can be dynamically created, destroyed, passed to a function, returned as a value, and have all the rights as other variables in the programming language have. Depending on the language, this can imply: being expressible as ...
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Group by multiple columns in dplyr, using string vector input

... Does the call to one_of() do anything here? I think it is redundant in this context, as the expression is wrapped in a call to vars(). – knowah Aug 15 '19 at 14:13 ...
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Anonymous recursive PHP functions

... pass it by reference. Be aware, that if you modify the $factorial before calling the function, the result will change as it's passed by reference. – Marius Balčytis Sep 13 '12 at 21:48 ...
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Change column type from string to float in Pandas

...ost) any other type (even if it's not necessarily sensible to do so). Also allows you to convert to categorial types (very useful). infer_objects() - a utility method to convert object columns holding Python objects to a pandas type if possible. convert_dtypes() - convert DataFrame columns to the ...
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Is it possible to have multiple statements in a python lambda expression?

...Q. Can you put multiple statements in a lambda? A. No. But you don't actually need to use a lambda. You can put the statements in a def instead. i.e.: def second_lowest(l): l.sort() return l[1] map(second_lowest, lst) Q. Can you get the second lowest item from a lambda by sorting the ...
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What's a good way to extend Error in JavaScript?

...nvironments set the stack property, but fileName and lineNumber are practically useless to be used in inheritance. So, the minimalistic approach is: function MyError(message) { this.name = 'MyError'; this.message = message; this.stack = (new Error()).stack; } MyError.prototype = new Er...