Question

I have a column in a dataframe like this:

npt2$name
#  [1] "Andreas Groll, M.D."
#  [2] ""
#  [3] "Pan-Chyr Yang, PHD"
#  [4] "Suh-Fang Jeng, Sc.D"
#  [5] "Mostafa K Mohamed Fontanet Arnaud"
#  [6] "Thomas Jozefiak, M.D."
#  [7] "Medical Monitor"
#  [8] "Qi Zhu, MD"
#  [9] "Holly Posner"
# [10] "Peter S Sebel, MB BS, PhD Chantal Kerssens, PhD"
# [11] "Lance A Mynderse, M.D."
# [12] "Lawrence Currie, MD"

I tried gsub but with no luck.
After doing toupper(x) I need to replace all instances of ‘MD’ or ‘M.D.’ or ‘PHD’ with nothing.

Is there a nice short trick to do it?

In fact I would be interested to see it done on a single string and how differently it is done in one command on the whole list.

Answer 1

Either of these:

gsub("MD|M\\.D\\.|PHD", "", test)  # target specific strings
gsub("\\,.+$", "", test)        # target all characters after comma

Both Matt Parker above and Tommy below have raised the question whether ‘M.R.C.P.’, ‘PhD’, ‘D.Phil.’ and ‘Ph.D.’ or other British or Continental designations of doctorate level degrees should be sought out and removed. Perhaps @user56 can advise what the intent was.