Regular expressions & sub

Dear all,

I am struggling with the use of regular expression. I got

as.character(test$sample.id)

[1] "1.11"   "10.11"  "11.11"  "113.31" "114.2"  "114.3"  "114.8"  

and need

[1] "11"   "11"  "11"  "31" "2"  "3"  "8"

I.e. remove everything before the "." .

TIA,

Bernd