条件语句

R 中级

Filip Schouwenaars

DataCamp Instructor

if 语句

if(condition) {
  expr
}

x <- -3

if(x < 0) {
  print("x is a negative number")
}

"x 是负数"

if(condition) {
  expr
}

x <- 5

if(x < 0) {
  print("x is a negative number")
}

if(condition) {
  expr1
} else {
  expr2
}

x <- -3

if(x < 0) {
  print("x is a negative number")
} else {
  print("x is either a positive number or zero")
}

"x 是负数"

if(condition) {
  expr1
} else {
  expr2
}

x <- 5
if(x < 0) {
  print("x is a negative number")
} else {
  print("x is either a positive number or zero")
}

"x 要么是正数要么是 0"

if(condition1) {
  expr1
} else if(condition2) {
  expr2
} else {
  expr3
}

x <- -3

if(x < 0) {
  print("x is a negative number")
} else if(x == 0) {
  print("x is zero")
} else {
  print("x is a positive number")
}

"x 是负数"

x <- 0

if(x < 0) {
  print("x is a negative number")
} else if(x == 0) {
  print("x is zero")
} else {
  print("x is a positive number")
}

"x 是 0"

x <- 5

if(x < 0) {
  print("x is a negative number")
} else if(x == 0) {
  print("x is zero")
} else {
  print("x is a positive number")
}

"x 是正数"

x <- 6

if(x %% 2 == 0) {
  print("divisible by 2")
} else if(x %% 3 == 0) {
  print("divisible by 3")
} else {
  print("not divisible by 2 nor by 3...")
}

"可被 2 整除"

R 中级