[R] removing all non-numeric characters from a string, but not "."

[Marc Schwartz]

> On Jul 26, 2016, at 4:39 PM, Marc Schwartz <marc_schwartz at me.com> wrote:
> 
> 
>> On Jul 26, 2016, at 4:28 PM, Dimitri Liakhovitski <dimitri.liakhovitski at gmail.com> wrote:
>> 
>> Hello!
>> 
>> I have a string x:
>> x <- c("x - 84", "y - 293.04", "z = 12.5")
>> 
>> I want to remove all the non-numeric stuff from it. The following works:
>> gsub("[^0-9]", "", x)
>> 
>> However, it strips my numbers of "."
>> 
>> Help - how could I do the same but leave the "." in?
>> 
>> Thanks a lot!
>> 
>> -- 
>> Dimitri Liakhovitski
> 
> 
>> gsub("[^0-9\\.]", "", x)
> [1] "84"     "293.04" "12.5"  
> 
> The period needs to be escaped since it otherwise has special meaning in the regex.
> 
> Regards,
> 
> Marc Schwartz


Actually, let me correct my reply.

When in a character group, as is the case here, the period does not need to be escaped:

> gsub("[^0-9.]", "", x)
[1] "84"     "293.04" "12.5"  


Regards,

Marc