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

...t's the best resource for learning how to write C code for use with R? I know about the system and foreign language interfaces section of R extensions, but I find it pretty hard going. What are good resources (both online and offline) for writing C code for use with R? ...
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What is the best way to create constants in Objective-C

...ne my research and found several methods to create constants, but I don't know which one to use: 2 Answers ...
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ActiveModel::ForbiddenAttributesError when creating new user

...pecify in each controller) Additionally, load_and_authorize_resource can now take a param_method option to specify a custom method in the controller to run to sanitize input. You can associate the param_method option with a symbol corresponding to the name of a method that will get called: class...
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How to get Visual Studio 'Publish' functionality to include files from post build event?

...dsOn> </PropertyGroup> This will add our target to the process, now we need to define the target itself. Let’s assume that you have a folder named Extra Files that sits 1 level above your web project. You want to include all of those files. Here is the CustomCollectFiles target and we d...
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Split column at delimiter in data frame [duplicate]

... Also, is there a way to do it if you don't know the number of columns which would result? – The Red Pea Oct 26 '15 at 20:42 2 ...
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Fastest Way to Find Distance Between Two Lat/Long Points

...s of Geometry data types in MyISAM table. As of Mysql 5.7.5, InnoDB tables now also support SPATIAL indices. Create a SPATIAL index on these points Use MBRContains() to find the values: SELECT * FROM table WHERE MBRContains(LineFromText(CONCAT( '(' , @lon + 10 / ( 111.1 / cos...
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Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?

...ults, but we've ascertained that it's at least one-quarter of all inputs. Now let's look at a fixed-width (i.e. non-bignum) integer power function. For what portion inputs does it not simply overflow? To maximize the number of meaningful input pairs, the base should be signed and the exponent uns...
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PostgreSQL Autoincrement

... @Dr Deo : they use serial instead autoincrement keyword, i don't know why :) – Ahmad Jul 22 '12 at 7:16 4 ...
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Can someone explain the dollar sign in Javascript?

...them. There is another common meaning for a dollar sign in an interpreter nowadays: the jQuery object, whose name only consists of a single dollar sign ($). This is a convention borrowed from earlier Javascript frameworks like Prototype, and if jQuery is used with other such frameworks, there will...
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Primary key or Unique index?

...e a composed primary key (person_id, car_id)? – unbeknown Jan 28 '09 at 12:20 3 primary key (pers...