stringr for "replace all after first 2 digits after dot"

[Angel70]

I would like to replace all characters after the first two digits after a dot.

E.g. having a string of 1234.56789 should result into 1234.56.

I have been trying "str_replace" but I could not write a regular expression to make it right.

[HanOostdijk]

like this?

library(stringr)
x <- '1234.56789'
stringr::str_replace(x,"(?<=\\.\\d\\d)(.*)$","")  
#> [1] "1234.56"
Created on 2023-08-31 with reprex v2.0.2

[nirgrahamuk]

if you need this for digits before and after a dot, then this

str_replace(x,
            pattern = "(\\.[0-9]{2})[0-9]*", 
            replacement = "\\1")

whereas if its alphanumeric character then perhaps

str_replace(x,
           pattern = "(\\.[[:alnum:]]{2})[[:alnum:]]*", 
           replacement = "\\1")

[Angel70]

Thanks a lot for the answers. They work perfectly!