Basics Calculations in R Language

- > is the prompt sign in R


- The assignment operators are the left arrow with dash <- and equal sign =.
    > x <- 20 assigns the value 20 to x.
    > x = 20 assigns the value 20 to x.
    Initially only <- was available in R.


-  > x = 20 assigns the value 20 to x.
   > y = x + 2 assigns the value 2 * x to y.
   > z = x + y assigns the value x + y to z.


# : The character # marks the beginning of a comment. All characters until the end of the line are ignored.
  > # mu is the mean
  > # x <- 20 is treated as comment only.

Capital and small letters are different.
 > x <- 20 and > x <- 20 are different

The command c (1,2,3,4,5) combines the numbers 1,2,3,4 and 5 to a vector.

 R as a calculator
 
 > 2 + 3              # Command
 [1] 5                  # Output

  > 2 * 3              # Command
  [1]  6                 # Output

Multiplication and Division x * y , x/y

> c ( 2,3,5,7) * 3
[1]   6 9 15 21 

Addition and Subtraction x + y , x - y

> (2,3,5,7) + 10
[1] 12 13 15 17