anonymous function r
Guidelines. 1  Please try to keep submissions on topic and of high quality. 2  Just because it has a computer in it doesn't make it programming. 3  Memes and image macros are not acceptable forms of content.  If there is no code in your link, it probably doesn't belong 1  here. App demos should include code and/or architecture discussion. Functional programming in R. This post is based on a talk I gave at the Manchester R User Group on functional programming in R on May 2nd 2013. This post is about functional programming, why it is at the heart of the R language and how it can hopefully help you to write cleaner, faster and more bug-free R programs. Use anonymous functions. You can, of course, use any function you want for the FUN argument. That function doesn’t even need to have a name, because you effectively copy the code. So, instead of giving a function name, you can just add the code as an argument as an anonymous function. An anonymous function is a function without a name. Obtuse error messages and a variety of differing yet similar data structures leads to a frustrating learning curve. Furthermore R is a functional programming language which, if you are used to imperative programming (e.g. Java/Perl/Python/Ruby), makes R seem like a crufty Perl for statistics. The functional nature of R however is often understated. Anonymous Functions. As remarked at several points in this book, the purpose of the R function function() is to create functions. It instructs R to create a function that adds 1 to its argument and then assigns that function to inc. However, that last step—the assignment—is not always taken. R does allow for recursive functions and they can sometimes be useful, particularly in traversal of tree-like data structures, but recursion in not very efficient R (it is not tail-call optimised) and I will not discuss it further here, though it may well be the subject of a future post. Anonymous Functions. As remarked at several points in this book, the purpose of the R function function() is to create functions. For instance, consider this code: inc <- function(x) return(x+1) It instructs R to create a function that adds 1 to its argument and then assigns that function to inc. In R, you can pass a function itself as an argument. You can easily assign the complete code of a function to a new object. Similarly, you also can assign the function code to an argument. This opens up a complete new world of possibilities. What Are Anonymous Functions? An anonymous function is a function that is not stored in a program file, but is associated with a variable whose data type is function_handle. Anonymous functions can accept inputs and return outputs, just as standard functions do. However, they can contain only a single executable statement. Yes, it would be squaring the circle - sorry, I did not think this through! A function in C is just a pointer to code; a fat function pointer type would not be particularly elegant. Plain anonymous functions (like in the prepro discussed) are easy to reason about.
Anonymous Functions, as remarked at several points in this book, the purpose of the R function function() is to create functions. It instructs R to create a function that adds 1 to its argument and then assigns that function to inc. However, that last step the assignment is not always taken.