R Notebook

algorism 계산

x <- 7
y <- 5
x + y 
# 식으로 표현하기
cat(x,"+",y,"=",x+y)

plus <- function(x,y){
  return (x+y);
}
plus(3,8)

plus <- function(x,y){
  return (cat(x,"+",y,"=",x+y));
}
plus(3,8)

minus <- function(x,y){
  return (x-y);
}
minus(3,8)

multi <- function(x,y){
  return  (cat(x,"*", y, "=", x*y));
}
multi(3,8)

div.float <- function(x,y){
  return (cat(x,"/", y, "=", x/y));
}
div.float(8,3)

div.integer <- function(x,y){
  return (cat(x,"%/%", y, "=", x%/%y));
}
div.integer(8,3)

div.remainder <- function(x,y){
  return (cat(x,"%%", y, "=", x%%y));
}
div.remainder(8,3)


## 계산기
x <- 3
op <- "+"
y <-  2

if(op=="+") plus(x,y) else
if(op=="-") minus(x,y) else
if(op=="*") multi(x,y) else
if(op=="/") div.float(x,y) else
if(op=="%/%") div.integer(x,y) else
if(op=="%%") div.remainder(x,y) else
print("error")

calc <-  function(x,op,y){
  if(op=="+") plus(x,y) else
  if(op=="-") minus(x,y) else
  if(op=="*") multi(x,y) else
  if(op=="/") div.float(x,y) else
  if(op=="%/%") div.integer(x,y) else
  if(op=="%%") div.remainder(x,y) else
  print("error")
}

calc(1,"+",2)
calc(2,">",4)

# data 종류: count (이산형), countless (연속형)
calc2 <-  function(x,op,y){
  switch(
    op,
    "+"=plus(x,y),
    "-"=minus(x,y),
    "*"=multi(x,y),
    "/"=div.float(x,y),
    "%/%"=div.integer(x,y), 
    "%%"=div.remainder(x,y)
  )
}

calc2(5,"*",6)