R语言中mode、class、typeof区别

• mode

mode中将integer和double显示为numeric

• class

mode是指变量的类型如：数值型、字符型、逻辑型等
class是指变量的类别如：矩阵、列表、数据框等

• typeof

typeof是对变量类型的细分

查看下面的范例

x <- 1
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- letters
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- TRUE
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- cars
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- cars[1]
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- cars[[1]]
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- matrix(cars)
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- new.env()
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- expression(1 + 1)
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- quote(y <- 1 + 1)
print(c(class(x), mode(x), storage.mode(x), typeof(x)))

x <- ls
print(c(class(x), mode(x), storage.mode(x), typeof(x))) 

上方代码的运行结果

[1] "numeric" "numeric" "double" "double"
[1] "character" "character" "character" "character"
[1] "logical" "logical" "logical" "logical"
[1] "data.frame" "list" "list" "list"
[1] "data.frame" "list" "list" "list"
[1] "numeric" "numeric" "double" "double"
[1] "matrix" "list" "list" "list"
[1] "environment" "environment" "environment" "environment"
[1] "expression" "expression" "expression" "expression"
[1] "<-" "call" "language" "language"
[1] "function" "function" "function" "closure"