R 기초; 함수 Function

R 기초; 함수 Function

 

# 예시 함수 #01

transLength <- function(x) {

  tlength <- round(x*0.9144, digits=1)

  result <- paste(tlength, "m", sep="')

  return(result)

}

 

# 함수 적재

ls()

 

y <- c(100, 150, 200)

transLength(y)

[1] "91.4m" "137.2m" "182.9m"

 

trans2 <- transLength

trans2(y)

[1] "91.4m" "137.2m" "182.9m"

 

transLength <- function(x) {

  tlength <- round(x*0.9144, digits=1)

  result <- paste(tlength, "m", sep="')

}

 

print(transLength(y))

[1] "91.4m" "137.2m" "182.9m"

 

transLength <- function(x) {

  if((!is.numeric(x)))  return("Not a Number")

  tlength <- round(x*0.9144, digits=1)

  paste(tlength, "m", sep="")

}

 

transLength("ABC")

[1] "Not a Number"

 

# 함수 예시 #02

f1 <- function(x, y) {x + y}

f2 <- function(x, y) x + y

f1(1, 3)

[1] 4

f2(1, 3)

[1] 4

 

# 함수 예시 #03

transLength <- function(x, mult, unit) {

  tlength <- round(x*0.9144, digits=1)

  paste(tlength, "m", sep="")

}

 

transLength(y, mult=3, unit="ft")

[1] "300ft" "450ft" "600ft"

 

transLength(y, mult=3, unit="in")

[1] "3600in" "5400in" "7200in"

 

 

# 함수 예시 #04

transLength <- function(x, mult=0.9144, unit="m") {

  tlength <- round(x*0.9144, digits=1)

  paste(tlength, "m", sep="")

}

 

transLength(y)

[1] "91.4m" "137.2m" "182.9m"

 

transLength(y, mult=3, unit="ft")

[1] "300ft" "450ft" "600ft"

 

transLength(y, 3, "ft")

[1] "300ft" "450ft" "600ft"

 

 

# 함수 예시 #05

transLength <- function(x, mult=0.9144, unit="m", digits=1) {

  tlength <- round(x*0.9144, digits=digits)

  paste(tlength, "m", sep="")

}

 

transLength(y)

[1] "91.4m" "137.2m" "182.9m"