> student1
Student name: Fred 
Student grade: 98 78 76 86
> student1
Student name: Fred 
Student grade: 98 78 76 86
> typeof(student1)
[1] "double"
> class(student1)
[1] "student"
> print(student1)
Student name: Fred 
Student grade: 98 78 76 86
> source('~/Desktop/classes.R')
> addGrade.student(student1, 57)
[1] 98 78 76 86 57
> attributes(student1)
$name
[1] "Fred"

$class
[1] "student"

> source('~/Desktop/classes.R')
> addGrade.student(student1, 57)
Student name: Fred 
Student grade: 98 78 76 86 57
> student1
Student name: Fred 
Student grade: 98 78 76 86
> # This doesn't change student1!  Must still use assignment statement
> student1 <- addGrade.student(student1, 57)
> student1
Student name: Fred 
Student grade: 98 78 76 86 57
> 
> # This way of looking at R data structures as 'objects' with functions that 
> # can edit or do things with that object has a name:
> # Object-oriented programming
> source('~/Desktop/classes.R')
> getName.student(student1)
[1] "Fred"
> source('~/Desktop/classes.R')
> setName.student(student1, "Jenny")
Student name: Jenny 
Student grade: 98 78 76 86 57
> source('~/Desktop/classes.R')
> doctor1
numeric(0)
attr(,"class")
[1] "doctor"
> source('~/Desktop/classes.R')
> doctor1
Doctor name: 
> doctor1 <- setName.doctor(doctor1, "Pepper")
> doctor1
Doctor name: Dr. Pepper 
> source('~/Desktop/classes.R')
> setName(student1, "Johnny")
Student name: Johnny 
Student grade: 98 78 76 86 57
> setName(doctor1, "Johnny")
Doctor name: Dr. Johnny 
> length(c(1, 2, 3))
[1] 3
> length(list(1,4,5))
[1] 3
> length("string")
[1] 1
> # length(x) is an example of a generic function
> # x can be of many differnt types
> # and length(x) chooses the correct specific function in R to give the length for that type
> # We don't care how those specific funtions work for each type. We just use length(x)!
> print(student1)
Student name: Fred 
Student grade: 98 78 76 86 57
> print(doctor1)
Doctor name: 
> # Print is also a generic function
> 
> student1
Student name: Fred 
Student grade: 98 78 76 86 57
> unclass(student1)
[1] 98 78 76 86 57
attr(,"name")
[1] "Fred"
> source('~/Desktop/classes.R')
> Student("Jimmy", c(67, 98, 45, 78))
Student name: Jimmy 
Student grade: 67 98 45 78
> jimmyStudent <- Student("Jimmy", c(67, 98, 45, 78))
> jimmyStudent
Student name: Jimmy 
Student grade: 67 98 45 78