misbehavior with extract_numeric() from tidyr
On Mon, Apr 20, 2015 at 1:57 PM, arnaud gaboury
<arnaud.gaboury at gmail.com> wrote:
On Mon, Apr 20, 2015 at 6:09 PM, William Dunlap <wdunlap at tibco.com> wrote:
The hyphen without a following digit confuses tidyr::extract_numeric(). E.g.,
> extract_numeric("23 ft-lbs")
Warning message:
In extract_numeric("23 ft-lbs") : NAs introduced by coercion
[1] NA
> extract_numeric("23 ft*lbs")
[1] 23
See[0] for the reason on the minus in the regex. It is not a bug but a wish. I am honestly very surprised the maintainer decided to go with such a so simple solution for negative numbers. [0]https://github.com/hadley/tidyr/issues/20
Any heuristic is going to fail in some circumstances. If you want to be sure it's doing what you want for your use case, write the regular expression yourself. Hadley