Regular expression in R to remove the part of a string after the last space

问题

I would like to have a gsub expression in R to remove everything in a string that occurs after the last space. E.g. string="Da Silva UF" should return me "Da Silva". Any thoughts?

回答1:

You can use the following.

string <- 'Da Silva UF'
gsub(' \\S*$', '', string)

[1] "Da Silva"

Explanation:

            ' '
\S*         non-whitespace (all but \n, \r, \t, \f, and " ") (0 or more times)
  $         before an optional \n, and the end of the string

回答2:

Using $ anchor:

> string = "Da Silva UF"
> gsub(" [^ ]*$", "", string)
[1] "Da Silva"

来源：https://stackoverflow.com/questions/20497895/regular-expression-in-r-to-remove-the-part-of-a-string-after-the-last-space