tutils: Tom's UTILity functionS

Description Usage Arguments Value Author(s) See Also Examples

Extract first / last object

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first(x)

last(x)

`x`	`object` indexable by `[`

object of same mode as x

Thomas P. Harte

Extract, na.omit

  # from the following phrases
  str<- c("hello there", "how are you?")
  cat(paste(str), sep="\n")
  # extract the first words:
  sapply(strsplit(str, " "), first)
  # extract the last words:
  sapply(strsplit(str, " "), last)

  # in fact this is a very useful idiom, e.g. with stock tickers:
  tickers<- c("INDU Index", "USD Curncy")
  cat(paste(tickers), sep="\n")
  short.tickers<- sapply(strsplit(tickers, " "), first)
  short.tickers
  category<- sapply(strsplit(tickers, " "), last)
  category