Message-ID: <CF4484B5-8601-49B1-AC69-4F025AE0DD01@comcast.net>
Date: 2013-05-03T15:57:58Z
From: David Winsemius
Subject: Why can't R understand if(num!=NA)?
In-Reply-To: <CABcx46DOkqo+2njKqaFyaxBN7YRBj7YKn_r3TkQw1JUi9m4Tfg@mail.gmail.com>
On May 3, 2013, at 8:24 AM, jpm miao wrote:
> I have a program, when I write
>
> if(num!=NA)
>
> it yields an error message.
>
> However, if I write
>
> if(is.na(num)==FALSE)
>
> it works.
>
> Why doesn't the first statement work?
Read the "manual":
?"NA"
--
David Winsemius
Alameda, CA, USA