3. if function.R

#if function-------------------------------------------------

#if(logical statement){value if true}

a <- 5
if(a > 2){"a is greater than 2"}

a <- 1
if(a > 2){"a is greater than 2"}


#if(logical statement){value if true}else{value if false}

a <- 1
if(a > 2){"a is greater than 2"}else{"a is less than 2"}

#ifelse(logical condition,"value if true",value if false)

a < -1
ifelse(a > 2, "a is greater than 2", "a is less than 2")

#two or more conditions 4<a<10
a<-6
if(a<4){"a is less than 4"}else if(a<10){"a is between 4 and 10"}else
  {"a is greater than 10"}