String split with conditions in R

Question

I have this mystring with the delimiter _. The condition here is if there are two or more delimiters, I want to split at the second delimiter and if th

Answer 1

gsub('^(.*\\.\\d+).*','\\1',mystring)
[1] "MODY_60.2"   "MODY_116.21" "MODY_116.3"  "MODY_116.4"