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Bash, no-arguments warning, and case decisions
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I interpreted "and" as "otherwise", assuming that the message would be some help text. But I'm sure Werner is able to figure out what that line does and whether he wants it :)
– Thomas
Mar 11 '10 at 19...
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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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?
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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...
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...
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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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...
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...
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 reshape data from long to wide format
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+1 and you don't need to rely on external packages, since reshape comes with stats. Not to mention that it's faster! =)
– aL3xa
May 5 '11 at 0:07
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