将R代码中断到文件路径的下一行

Question

Why this works:

PC<-read.csv('./public-transportation/san-francisco/passenger-count.csv', header=TRUE)

But the following doesn't work in R:

inputFile <-paste('./public-transportation/',
'san-francisco/passenger-count.csv')
PC<-read.csv(inputFile, header=TRUE)

All I am doing is passing a variable that holds the filename? Sorry, I am relatively new to R. This is kinda baffling me a bit. Any help is appreciated..

Answer 1

This doesn't work because the default separator in paste is a space. So you need to set sep="" , use paste0 , or use file.path .

# paste with sep=""
inputFile <- paste('./public-transportation/',
  'san-francisco/passenger-count.csv', sep="")
# paste0
inputFile <- paste0('./public-transportation/',
  'san-francisco/passenger-count.csv')
# file.path
inputFile <- file.path('./public-transportation/',
  'san-francisco/passenger-count.csv')