Example fo Basic R :

In this post we discuss R Examples

Variable Declaration:

variable1 <- 14

(OR)

variable1 = 14

Remove variable:

rm(variable1)

List the variables:

ls()

Remove All Variables:

rm(list=ls())

Arithmetic Operator:

> a=10

> b=15

> a+b

> 25

Relational Operator:

> a=16

> b=27

> a > b

> FALSE

Logical Operator:

> a = TRUE > b = FALSE

> a|b

> TRUE

> a&b

> FALSE

Miscellaneous Operators:

> n=2:5

[1] 2 3 4

IF statement:

> a <- “Geoinsyssoft”

> if (is.character(a)) {

> print(“a is character”)

> }

[1] “a is character”

Switch statement:

> a <- switch(2, “one”,”two”,”three”,”four”)

> print(a)

[1] “two”

While Statement:

> a <- c(“HI”, “This is Geoinsyssoft”)

> n <- 6

> while(n>=0) {

> print(a)

> n=n-1

> }

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

[1] “HI” “This is Geoinsyssoft”

FOR statement:

> v <- 1:6

> for (i in v ) {

> print(“Welcome to Geoinsysoft”)

> }

[1] “Welcome to Geoinsysoft”

[1] “Welcome to Geoinsysoft”

[1] “Welcome to Geoinsysoft”

[1] “Welcome to Geoinsysoft”

[1] “Welcome to Geoinsysoft”

[1] “Welcome to Geoinsysoft”

Built-in Function:

Sequence Function:

> print(seq(32,44))

[1] 32 33 34 35 36 37 38 39 40 41 42 43 44

Mean:

> print(mean(25:82))

[1] 53.5

User-defined Function:

> c <-2

> new.function <- function(a) {

> for(i in 1:a) {

> b <- i^(2*c)

> print(b)

> }

> }

> new.function(2)

[1] 1

[1] 16

Mean:

> a <- c(10,18,30,29,340,29)

> mean(a)

[1] 76

Median:

> sort(a)

[1] 10 18 29 29 30 340

> median(sort(a))

[1] 29

List:

> list_data <- list(“Red”, “Green”, c(1,2,3), TRUE, 5, 9.2)

> list_data

[[1]]

[1] “Red”

[[2]]

[1] “Green”

[[3]]

[1] 1 2 3

[[4]]

[1] TRUE

[[5]]

[1] 5

[[6]]

[1] 9.2

Matrics:

Create Matrix

> a <- matrix(c(1:12), nrow = 4, byrow = TRUE)

> a

[,1] [,2][,3]
[1,] 1 2 3
[2,] 4 5 6
[3,] 7 8 9
[4,] 10 11 12

Give name to the row and column

> dimnames(a)=list(c(“row1″,”row2″,”row3″,”row4”),c(“col1″,”col2″,”col3”))

> a
col1 col2 col3
row1 1 5 9
row2 2 6 10
row3 3 7 11
row4 4 8 12

Select Particular value

> print(a[4,3])

[1] 12

Matrix Multiplication

> a <- matrix(c(1:12), nrow = 4, byrow = TRUE)

> b <- matrix(c(5:16), nrow = 4, byrow = TRUE)
> c <- a*b
> c
[,1] [,2] [,3]
[1,] 5 12 21
[2,] 32 45 60
[3,] 77 96 117
[4,] 140 165 192

Array:

Creating Array

> a<-c(10,20,30,40)

> b<-c(20,30,40,50,60,70,80,90)
> c<-array(c(a,b),dim=c(5,5,3))
> c
, , 1

[,1] [,2] [,3] [,4] [,5]
[1,] 10 30 80 40 60
[2,] 20 40 90 20 70
[3,] 30 50 10 30 80
[4,] 40 60 20 40 90
[5,] 20 70 30 50 10

, , 2

[,1] [,2] [,3] [,4] [,5]
[1,] 20 40 90 20 70
[2,] 30 50 10 30 80
[3,] 40 60 20 40 90
[4,] 20 70 30 50 10
[5,] 30 80 40 60 20

, , 3

[,1] [,2] [,3] [,4] [,5]
[1,] 30 50 10 30 80
[2,] 40 60 20 40 90
[3,] 20 70 30 50 10
[4,] 30 80 40 60 20
[5,] 40 90 20 70 30

Factor:

Create Factor

> b<-factor(a)

> b
[1] 10 20 30 40
Levels: 10 20 30 40

Factor Using Data Frame

> Height <- c(132,151,162,139,166,147,122)

> Weight <- c(48,49,66,53,67,52,40)
> Name <- c(“aaa”,”bbb”,”ccc”,”ddd”,”eee”,”fff”,”ggg”)
> a <- data.frame(Name,Height,Weight)
> a
Name Height Weight
1 aaa 132 48
2 bbb 151 49
3 ccc 162 66
4 ddd 139 53
5 eee 166 67
6 fff 147 52
7 ggg 122 40

> print(is.factor(a\$Name))
[1] TRUE

> print((a\$Name))
[1] aaa bbb ccc ddd eee fff ggg
Levels: aaa bbb ccc ddd eee fff ggg