R: The R Project for Statistical Computing
Basic Arithmetic Calculation
> 1+3/5
[1] 1.6
> print(3)
[1] 3
Comment - #
> # This is a comment
Combine Values into a Vector or List - c (data)
> x <- c(2,5,7,8,10)
Return number of data - length(data)
> length(x)
Sorting data - sort (data)
> sort(x)
Data Frame
> name <- c("James", "Kate", "Henry")
> gender <- c("Male", "Female", "Male")
> age <- c(18, 25, 35)
> persons <- data.frame(name, gender, age)
name gender age
1 James Male 18
2 Kate Female 25
3 Henry Male 35
Refer to a Data Frame
> summary(persons$age) #using $
Min. 1st Qu. Median Mean 3rd Qu. Max.
18.0 21.5 25.0 26.0 30.0 35.0
> with(persons,{ #using with
summary(age)
})
Min. 1st Qu. Median Mean 3rd Qu. Max.
18.0 21.5 25.0 26.0 30.0 35.0
Showing Structure of a Data Frame
> str(persons)
'data.frame': 3 obs. of 3 variables:
$ name : chr "James" "Kate" "Henry"
$ gender: chr "Male" "Female" "Male"
$ age : num 18 25 35