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Convert a list to a data frame
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Update July 2020:
The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns...
Convert a PHP script into a stand-alone windows executable
...ritten a small PHP script which I run from the command line using PHP-CLI. Now I want to hand over this script to someone but I do not want to:
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Make Vim show ALL white spaces as a character
...l, in combination with
:set listchars=...
display invisible characters.
Now, there isn't an explicit option which you can use to show whitespace, but in listchars, you could set a character to show for everything BUT whitespace. For example, mine looks like this
:set listchars=eol:$,tab:>-,tr...
Error installing mysql2: Failed to build gem native extension
...with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.5\include"'
Now the gem should have installed correctly
Lastly copy the libmysql.dll file from
C:\Program Files\MySQL\MySQL Server 5.5\lib
to
C:\Rails\Ruby1.9.2\bin
--- Install the mysql2 Gem ---
You will now be able to u...
What is event bubbling and capturing?
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useCapture now supported in IE >= 9. source
– beatgammit
Aug 20 '13 at 17:10
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What is the curiously recurring template pattern (CRTP)?
...ss A : public X<A> {...};
It is curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <cl...
How do I clone a Django model instance object and save it to the database?
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Worth noting that this quotes Django 1.2, we're now up to Django 1.4. Haven't tested whether or not this works, but don't use this answer without being sure that it works for you.
– Joe
Oct 4 '12 at 11:37
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Why doesn't .NET/C# optimize for tail-call recursion?
...s support tail call optimization, but the language-specific compiler must know how to generate the relevant opcode and the JIT must be willing to respect it.
F#'s fsc will generate the relevant opcodes (though for a simple recursion it may just convert the whole thing into a while loop directly). C#...
How to detect if multiple keys are pressed at once using JavaScript?
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Note: keyCode is now deprecated.
Multiple keystroke detection is easy if you understand the concept
The way I do it is like this:
var map = {}; // You could also use an array
onkeydown = onkeyup = function(e){
e = e || event; // to deal w...
This app won't run unless you update Google Play Services (via Bazaar)
...nt.
(The comment is from Zhelyazko Atanasov yesterday at 23:18, I don't know how to link directly to it)
Also, you don't see the "(via Bazaar)" part when running from an actual device, and the update button open the Play Store. I am assuming Bazaar is meant to provide Google Play Services on the ...