Lesson 1 basic

1.3 function

round(3.1415)

## [1] 3

factorial(5)  # 5! = 5*4*3*2*1

## [1] 120

mean(1:6)    #mean:平均、　関数に渡すデータは関数の引数（argument)と呼ぶ

## [1] 3.5

die <- 1:6
mean(die)

## [1] 3.5

sample(x = 1:4, size = 2)

## [1] 1 2

sample(x = die, size = 1)

## [1] 2

sample(x = die, size = 1)

## [1] 5

sample(x = die, size = 1)

## [1] 6

sample(die, size = 1)  

## [1] 5

# Xの指定は、どの引数にどのデータを割り当てるかを指定していた  
# 順番が決まっているので、省略することが可能  
args(sample)

## function (x, size, replace = FALSE, prob = NULL) 
## NULL

args(round)

## function (x, digits = 0) 
## NULL

round(3.1415, digits = 2)

## [1] 3.14

sample(die, 1)

## [1] 3

sample(size =1, x = die)

## [1] 5