Works from CLI but not from prompt

My objective is to define a pattern for a grep() statement.

Thanks,
Henri-Paul

You are not illustrating the problem with enough detail to determine  
the source of your errors. The errors do not appear when tested in  
what appears to be the obvious manner:

 > pt1  <- "[Aa]ccountability"
 > grep(pt1, "accountability")
[1] 1
 > grep(pt1, "Accountability")
[1] 1
 > grep(pt1, "countability")
integer(0)

An old advertisement in TV in the US used to ask: "Where's the Beef?"

David Winsemius, MD
West Hartford, CT