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Unique combination of all elements from two (or more) vectors
I am trying to create a unique combination of all elements from two vectors of different size in R.
5 Answers
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Memory footprint of Haskell data types
... GHC creates a single instance of these constructors and shares it amongst all uses.
A word is 4 bytes on a 32-bit machine, and 8 bytes on a 64-bit machine.
So e.g.
data Uno = Uno a
data Due = Due a b
an Uno takes 2 words, and a Due takes 3.
The Int type is defined as
data Int = I# Int#
no...
All falsey values in JavaScript
...RemoteJob)
"", '' and `` - strings of length 0
null
undefined
NaN
document.all (in HTML browsers only)
This is a weird one. document.all is a falsey object, with typeof as undefined. It was a Microsoft-proprietory function in IE before IE11, and was added to the HTML spec as a "willful violation ...
What are all the possible values for HTTP “Content-Type” header?
...urce).
As you can see the list is way too big for you to validate against all of them. What you can do is validate against the general format and the type attribute to make sure that is correct (the set of options is small) and just assume that what follows it is correct (and of course catch any ex...
How can I make pandas dataframe column headers all lowercase?
I want to make all column headers in my pandas data frame lower case
5 Answers
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Creating a favicon [closed]
...out favicons, I discovered I needed more than 10 kinds of files to work in all browsers and devices :(
I got pissed and created my own favicon generator, that creates all these files and the correct HTML header for each one of them: faviconit.com
Hope you enjoy it.
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How do I temporarily disable triggers in PostgreSQL?
I'm bulk loading data and can re-calculate all trigger modifications much more cheaply after the fact than on a row-by-row basis.
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What is the motivation for bringing Symbols to ES6?
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Most languages (all mainstream ones afaik) provide some mechanism, usually reflection, to get access to private anyway.
– Esailija
May 14 '14 at 10:58
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Multiple file extensions in OpenFileDialog
...te groups so JPG are *.jpg and *.jpeg, TIFF are *.tif and *.tiff and also 'All graphic types'? How can I do that?
3 Answers...
SQL Logic Operator Precedence: And and Or
...en if they are not needed. very few programers (if any) know precedence of all operators available.
– Trismegistos
Nov 6 '13 at 11:45
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