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Where can I learn how to write C code to speed up slow R functions? [closed]

...: SEXP foobar(){ SEXP ab; PROTECT(ab = allocVector(STRSXP, 2)); SET_STRING_ELT( ab, 0, mkChar("foo") ); SET_STRING_ELT( ab, 1, mkChar("bar") ); UNPROTECT(1); } Using Rcpp, you can write the same function as: SEXP foobar(){ return Rcpp::CharacterVector::create( "foo", "bar" ) ; } ...
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How to call a PHP function on the click of a button

...essfully"); }); }); }); In ajax.php <?php if (isset($_POST['action'])) { switch ($_POST['action']) { case 'insert': insert(); break; case 'select': select(); break; } } ...
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Django FileField with upload_to determined at runtime

...ng to set up my uploads so that if user joe uploads a file it goes to MEDIA_ROOT/joe as opposed to having everyone's files go to MEDIA_ROOT. The problem is I don't know how to define this in the model. Here is how it currently looks: ...
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Unsupported major.minor version 52.0 [duplicate]

...l Java 1.5 and is nowadays called "Java SE", see en.wikipedia.org/wiki/Java_Platform,_Standard_Edition – Tim Büthe Sep 6 '16 at 14:38 1 ...
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Scala equivalent of Java java.lang.Class Object

...: java.lang.Class[C] = class C scala> c.getClass res1: java.lang.Class[_] = class C That is why the following will not work: val xClass: Class[X] = new X().getClass //it returns Class[_], nor Class[X] val integerClass: Class[Integer] = new Integer(5).getClass //similar error There is a ticket...
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Apply multiple functions to multiple groupby columns

...ame, you can use a normal function and supply a custom name to the special __name__ attribute like this: def max_min(x): return x.max() - x.min() max_min.__name__ = 'Max minus Min' df.groupby('group').agg({'a':['sum', 'max'], 'b':'mean', 'c'...
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When to use self over $this?

...on-static and static member variables: <?php class X { private $non_static_member = 1; private static $static_member = 2; function __construct() { echo $this->non_static_member . ' ' . self::$static_member; } } new X(); ?> Here is an example of incorr...
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Is gettimeofday() guaranteed to be of microsecond resolution?

...fectively makes the answer to your question no. You should look into clock_gettime(CLOCK_MONOTONIC) for timing intervals. It suffers from several less issues due to things like multi-core systems and external clock settings. Also, look into the clock_getres() function. ...
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Can I use Twitter Bootstrap and jQuery UI at the same time?

...no] - jquery-ui-1.9.2.custom.min.css [images] - ui-bg_diagonals-thick_90_eeeeee_40x40.png - ui-bg_glass_100_e4f1fb_1x400.png - ui-bg_glass_50_3baae3_1x400.png - ui-bg_glass_80_d7ebf9_1x400.png - ui-bg_highlight-hard_100_f2f5f7_1x100.png ...
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Converting a view to Bitmap without displaying it in Android?

...( v.getLayoutParams().width, v.getLayoutParams().height, Bitmap.Config.ARGB_8888); Canvas c = new Canvas(b); v.layout(v.getLeft(), v.getTop(), v.getRight(), v.getBottom()); v.draw(c); return b; } if the view wasn't displayed before the size of it will be zero. Its p...