Executing two separate codes on the basis of conditions

Question

I am having problem with the following codes (I'm a beginner, so please go easy on me):

COW$id<- (COW$tcode1*1000 + COW$tcode2)
COW$id<- (COW$tcode2*1000 + COW$tcode1)

I want the first line of code to be executed on the condition that the value of tcode1 (a variable in COW dataframe) is less than tcode2 (tcode1 < tcode2), and I want the second line of code to be executed if tcode1 is greater than tcode2 (tcode1 > tcode2). The end result I am looking for is a single column "ID" in my dataframe, on the basis of the conditions above. Does anyone know how to achieve this?

Answer 1

COW = data.frame(tcode1=c(5,7,18,9),tcode2=c(4,15,8,10))
head(COW)

  tcode1 tcode2
      5      4
      7     15
     18      8
      9     10

id = ifelse(COW$tcode1<COW$tcode2,
            COW$tcode1*1000 + COW$tcode2,
            COW$tcode2*1000 + COW$tcode1)

COW = data.frame(id=id,COW)
head(COW)

  id tcode1 tcode2
4005      5      4
7015      7     15
8018     18      8
9010      9     10