R Operators - r - learn r - r programming
- R has several operators to perform tasks including arithmetic, logical and bitwise operations.
- R has many operators to carry out different mathematical and logical operations.
- Operators in R can mainly be classified into the following categories.
R Arithmetic Operators
- These operators are used to carry out mathematical operations like addition and multiplication. Here is a list of arithmetic operators available in R.
Arithmetic Operators in R
| Operator | Description |
|---|---|
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| / | Division |
| ^ | Exponent |
| %% | Modulus (Remainder from division) |
| %/% | Integer Division |
Read Also
Operator PrecedenceExample
> x <- 5
> y <- 16
>x+y
[1] 21
> x-y
[1] -11
> x*y
[1] 80
> y/x
[1] 3.2
> y%/%x
[1] 3
> y%%x
[1] 1
>y^x
[1] 1048576
Types of operators
- Assignment Operator.
- Mathematical Operators.
- Relational Operators.
- Logical Operators.
- Bitwise Operators.
- Shift Operators.
- Unary Operators.
- Ternary Operator.
R Relational Operators
- Relational operators are used to compare between values. Here is a list of relational operators available in R.
| Operator | Description |
|---|---|
| < | Less than |
| > | Greater than |
| <= | Less than or equal to |
| >= | Greater than or equal to |
| == | Equal to |
| != | Not equal to |
Example:
> x <- 5
> y <- 16
> x<y
[1] TRUE
> x>y
[1] FALSE
> x<=5
[1] TRUE
> y>=20
[1] FALSE
> y == 16
[1] TRUE
>x != 5
[1] FALSE
Operation on Vectors
- The above mentioned operators work on vectors. The variables used above were in fact single element vectors.
- We can use the function c() (as in concatenate) to make vectors in R.
- All operations are carried out in element-wise fashion.
Here is an example.
> x <- c(2,8,3)
> y <- c(6,4,1)
>x+y
[1] 8124
> x>y
[1] FALSE TRUETRUE
- When there is a mismatch in length (number of elements) of operand vectors, the elements in shorter one is recycled in a cyclic manner to match the length of the longer one.
- R will issue a warning if the length of the longer vector is not an integral multiple of the shorter vector.
> x <- c(2,1,8,3)
> y <- c(9,4)
>x+y# Element of y is recycled to 9,4,9,4
[1] 115177
> x-1# Scalar 1 is recycled to 1,1,1,1
[1] 1072
>x+c(1,2,3)
[1] 33114
Warning message:
In x + c(1, 2, 3) :
longer object length isnot a multiple of shorter object length
R Logical Operators
- Logical operators are used to carry out Boolean operations like AND, OR etc.
| Operator | Description |
|---|---|
| ! | Logical NOT |
| & | Element-wise logical AND |
| && | Logical AND |
| | Element-wise logical OR | Element-wise logical OR |
| || Logical OR | Logical OR |
- Operators & and | perform element-wise operation producing result having length of the longer operand.
- But && and || examines only the first element of the operands resulting into a single length logical vector.
- Zero is considered FALSE and non-zero numbers are taken as TRUE.
Example:
> x <- c(TRUE,FALSE,0,6)
> y <- c(FALSE,TRUE,FALSE,TRUE)
> !x
[1] FALSE TRUETRUE FALSE
>x&y
[1] FALSE FALSEFALSE TRUE
> x&&y
[1] FALSE
>x|y
[1] TRUETRUE FALSE TRUE
> x||y
[1] TRUE
R Assignment Operators
- These operators are used to assign values to variables.
| Operator | Description |
|---|---|
| <-, <<-, = | Leftwards assignment |
| ->, ->> | Rightwards assignment |
- The operators <- and = can be used, almost interchangeably, to assign to variable in the same environment.
- The <<- operator is used for assigning to variables in the parent environments (more like global assignments).
- The rightward assignments, although available are rarely used.
> x <- 5
> x
[1] 5
> x = 9
> x
[1] 9
>10 -> x
> x
[1] 10