[R] rename cols

[Anupam Tyagi]

For a newcomer who wants to rename variable "fksm" and "klmk" in a dataframe of
with 439 variables there is not easy and intuitive solution. That person has to
spend a lot of time listing columns and counting columns or doing string
searches or using brackets within brackets within brackets to get a simple thing
done. Is there a simple function or solution to this in R without using an
add-on package?