[R] how to test the existence of a name in a dataframe

Wolfram Fischer wolfram at fischer-zim.ch
Tue Dec 7 09:47:13 CET 2004


I wanted to test if there exists already a name (which is
incidentally a substring of another name) in a dataframe.
I did e.g.:

> data(swiss)
> names(swiss)
[1] "Fertility"        "Agriculture"      "Examination"      "Education"       
[5] "Catholic"         "Infant.Mortality"

> ! is.null(swiss$EduX)
[1] FALSE

> ! is.null(swiss$Edu)
[1] TRUE

I did not expect to get TRUE here because ``Edu'' does not exist
as name of ``swiss''.

I did finally:
> 'Edu' %in% names(swiss)
for which I got the expected FALSE.

My question: What is the recommended way to do such a test?

Thanks - Wolfram Fischer




More information about the R-help mailing list