[R] building data object on iteration

[Uwe Ligges]

Fred J. wrote:
> Hello
> I need help, few days tying to work this out but
> unable to find examples. "alos would appricate
> direction on how to find exmples"
> getting the file name "without the extension" into a
> character vector.
> for (i in dir("c:/data/")){
>     filename <- c(filename,sub("([^.]+)(\\..+)","\\1",
> i))
> }
> Error: Object "filename" not found
> and I understand why the error but cann't find a way
> to fix it.
> 
> thanks
> 
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You don't need a loop:

  filename <- sub("([^.]+)(\\..+)", "\\1", dir("c:/data/"))


Uwe Ligges


PS: Just to get your loop working (you don't want to do it that way!):

  filename <- NULL
  for (i in dir("c:/data/")){
      filename <- c(filename,sub("([^.]+)(\\..+)","\\1", i))