Saturday, April 28, 2012

How to write, save, and call your own functions in R With an Example

·         How to write?
                General form of function is
NameOfFun <- function(argument1,argument2...)
                        Your expressions go here
name <- function(x,y,..)
                        if(.....) do something to x and or y
                        if(.....) do something to ............
·         How to save?
                1- From R, write or paste your function code in R Editor or R script
                2- Save your function as "nameOfFile.R" in your working directory
·         How to Call?
1-  in R Console type source("nameOfFile.R")

I have written a function that automatically assign letter grades. You can copy the function from
Or you can follow the following steps that may help you to know how to call a function:-
1- Download the function from
2- Unzip the folder and copy the file "GradingFunction.R" into your working Directory
3- Go to R, and type
source("GradingFunction.R") to call the function
4- If you are a TA and would like to try the function in your classes, follow the arguments of function as explained here
5- I have also randomly generated grades if you wish to try the function. There are two examples from the above link.

Note: This function may not directly related  to Data Analysis, but the process is the same (e.g., you want to assign labels into your grouping variables if conditions satisfied) 


No comments:

Post a Comment