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Split comma-separated strings in a column into separate rows
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This old question frequently is being used as dupe target (tagged with r-faq). As of today, it has been answered three times offering 6 different approaches but is lacking a benchmark as guidance which of the approaches is the fastest1.
The benchmarked so...
What are the most interesting equivalences arising from the Curry-Howard Isomorphism?
...somorphism relatively late in my programming life, and perhaps this contributes to my being utterly fascinated by it. It implies that for every programming concept there exists a precise analogue in formal logic, and vice versa. Here's a "basic" list of such analogies, off the top of my head:
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MySQL: Quick breakdown of the types of joins [duplicate]
I would like a quick breakdown of the types of MySQL joins. I know of these, the rest I am not sure what they mean.
3 Answe...
What is “lifting” in Haskell?
I don't understand what "lifting" is. Should I first understand monads before understanding what a "lift" is? (I'm completely ignorant about monads, too :) Or can someone explain it to me with simple words?
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Difference between InvariantCulture and Ordinal string comparison
When comparing two strings in c# for equality, what is the difference between InvariantCulture and Ordinal comparison?
9 An...
Converting file size in bytes to human-readable string
I'm using this function to convert a file size in bytes to a human-readable file size:
19 Answers
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What issues should be considered when overriding equals and hashCode in Java?
What issues / pitfalls must be considered when overriding equals and hashCode ?
11 Answers
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Modifying a subset of rows in a pandas dataframe
Assume I have a pandas DataFrame with two columns, A and B. I'd like to modify this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
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Why have header files and .cpp files? [closed]
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Well, the main reason would be for separating the interface from the implementation. The header declares "what" a class (or whatever is being implemented) will do, while the cpp file defines "how" it will perform those features.
This reduces dependenc...
Cartesian product of multiple arrays in JavaScript
...nilla JS
Original 2017 Answer: 2-line answer with vanilla JS:
(see updates below)
All of the answers here are overly complicated, most of them take 20 lines of code or even more.
This example uses just two lines of vanilla JavaScript, no lodash, underscore or other libraries:
let f = (a, b) => []...