View source for Basics in R programming

==Importing and exporting  data in '''R'''==

'''R''' allows data importing from many different source formats. The most common used functions to import data are the ''read'' functions. The following code can be used to import a .csv table named "forest-data.csv" from the folder "my-working-folder". The data is stored in an object named ''data''.
<source lang="rsplus">
data <- read.csv("C:/Program Files/... /my-working-folder/forest-data.csv")
</source>
Note that ''/'' or ''\\'' instead of ''\'' is used in '''R''' to define the the file path in your computer.

A more convenient way of working is defining first the working directory from where the data will be imported and where the result can be stored. The actual working directory can be consulted by ''getwd()'', and the objects contained there by ''dir()''. The working directory can be defined as described below.
<source lang="rsplus">
setwd("D:/Data/... /R-course/")
</source>
Once defined the working directory, the file can be imported without specifying the file path as follows:
<source lang="rsplus">
data <- read.csv("forest-data.csv")
</source>
All the objects created or imported to '''R''' are temporary stored in the '''R'''-workspace. Objects in the workspace can be removed by  using the ''rm()'' function. All objects in the workspace are usually lost after finishing the '''R''' session. The easiest option to store 
permanently an object in the working directory is by using the ''write()'' functions. The code to save as a .csv file the object ''d'' 
is shown below.
<source lang="rsplus">
write.csv(d, "Data-saved.csv")
</source>