For ease of use, learn R programming by writing “Hello World!” (Hello, world!) Let’s start. Depending on your needs; You can write your own program; Write the program in the R command or use the R script for this purpose.
Syntax training R, Let’s look at both.
$ R
This will launch R interpreter and you will get to prompt> where you can type your program as follows:
> myString <- “Hello, World!”
> print (myString)
[1] “Hello, World!”
Here, the first expression defines a string variable; Where we assign the phrase “Hello World” to the string variable and then the print () statement is used to print the value stored in the myString variable.
R script file
Usually you will do your programming by writing your programs in script files and then with the help of interpreter R which calls Rscript; Run those scripts in the prompt command. So; Let’s do the following; Let’s start by writing the following code in the text file that test.R calls:
# My first program in R Programming
myString <- “Hello, World!”
print (myString)
Save the above code to a test.R file and run it on the Linux command line as shown below. Even if you use Windows and other systems; The syntax you use; It’s the same.
$ Rscript test.R
When we run the above program; The following result is obtained:
[1] “Hello, World!”
Comments
Comments are the same as the help text in your R program while your actual program is running; These comments are ignored by the program interpreter. Single line comment like below; Using # at the beginning of the phrase; It is written:
# My first program in R Programming
R programming does not support multi-line comments, but you can use a trick that looks something like this:
if (FALSE) {
“This is a demo for multi-line comments and it should be put inside either a
single OR double quote ”
}
myString <- “Hello, World!”
print (myString)
[1] “Hello, World!”
Although the above comments are executed by the R program interpreter; But they do not interfere with your actual program. You should put these types of comments either in one quote or in two quotes.