有没有大佬可以帮我看看这个语句有什么问题呀？



setwd("D:/R_edu/data")
loans=read.csv("loans.csv")
if (loans$status == "A"){loans$bad_good <-0
}else if (loans$status == "B") {loans$bad_good <-1
}else if (loans$status == "D") {loans$bad_good <-1
}else{
  loans$bad_good <-NA
}

报错：
Warning messages:
1: In if (loans$status == "A") { :
  the condition has length > 1 and only the first element will be used
2: In if (loans$status == "B") { :
  the condition has length > 1 and only the first element will be used



谢谢大佬