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How to make lists contain only distinct element in Python? [duplicate]
...g aspect of this new implementation is considered an implementation detail and should not be relied upon". Since they're both based on hashes, I'd think set would be the same, but it's not mentioned, so apparently not: docs.python.org/3.6/whatsnew/3.6.html
– Mark
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What's the difference between integer class and numeric class in R
...t common of which are double (for double precision floating point numbers) and integer. R will automatically convert between the numeric classes when needed, so for the most part it does not matter to the casual user whether the number 3 is currently stored as an integer or as a double. Most math ...
In Matlab, when is it optimal to use bsxfun?
...ng
Using bsxfun, like using accumarray, makes me feel good about my understanding of Matlab.
bsxfun will replicate the input arrays along their "singleton dimensions", i.e. the dimensions along which the size of the array is 1, so that they match the size of the corresponding dimension of the othe...
quick random row selection in Postgres
... that contains couple of millions of rows. I have checked on the internet and I found the following
7 Answers
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A semantics for Bash scripts?
...ripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is everything a string? What is the...
How to check if DST (Daylight Saving Time) is in effect, and if so, the offset?
...code uses the fact that getTimezoneOffset returns a greater value during Standard Time versus Daylight Saving Time (DST). Thus it determines the expected output during Standard Time, and it compares whether the output of the given date the same (Standard) or less (DST).
Note that getTimezoneOffset...
Find MongoDB records where array field is not empty
... To me that's the correct approach, since it makes sure the array exists and is not empty.
– LeandroCR
Mar 19 '15 at 14:34
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JSON left out Infinity and NaN; JSON status in ECMAScript?
Any idea why JSON left out NaN and +/- Infinity? It puts Javascript in the strange situation where objects that would otherwise be serializable, are not, if they contain NaN or +/- infinity values.
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How to install the current version of Go in Ubuntu Precise
...e GVM for managing my Go versions in my Ubuntu box. Pretty simple to use, and if you're familiar with RVM, it's a nobrainer. It allows you to have multiple versions of Go installed in your system and switch between whichever version you want at any point in time.
Install GVM with:
sudo apt-get i...
Split string into an array in Bash
In a Bash script I would like to split a line into pieces and store them in an array.
22 Answers
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