R中的ifelse'意外符号'错误

Question

Its just a basic ifelse but its returning the error: "unexpected symbol" and points to the first character of the last line. any ideas?

input1<-readline("using C:/Users/HouseGroup/Desktop/betterformat.csv as the target csv file.
  Is this correct?  Y/N" )
ifelse (input1=="Y",
theData <- read.csv("C:/Users/HouseGroup/Desktop/betterformat.csv"),
rightDir<- readline("please input the proper file path") 
theData<-  read.csv(rightDir))

Answer 1

You should use the standard if and else construct in R, as defined by the R language definition .

When the if statement is not in a block the else, if present, must appear on the same line as the end of statement2. Otherwise the new line at the end of statement2 completes the if and yields a syntactically complete statement that is evaluated. A simple solution is to use a compound statement wrapped in braces, putting the else on the same line as the closing brace that marks the end of the statement

if (input1=="Y") {
  theData <- read.csv("C:/Users/HouseGroup/Desktop/betterformat.csv")
} else {
  rightDir <- readline("please input the proper file path") 
  theData <- read.csv(rightDir)
}

The command ifelse takes vectors and returns vectors. See ?ifelse for examples.

x <- c(6:-4)
sqrt(x)  #- gives warning
sqrt(ifelse(x >= 0, x, NA))  # no warning