length of empty string

An embedded and charset-unspecified text was scrubbed...
Name: not available
URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20111118/14ee1b6c/attachment.pl>
Le vendredi 18 novembre 2011 ? 16:09 +0100, Jaensch, Steffen [TIBBE] a
?crit :
Hi all,

Can somebody explain why length("") returns 1 and not 0?
Probably because it contains one element, "".
How do I test if a given string is the empty string?
a <- ""
a == ""
[1] TRUE

Seems to be enough to me. ;-)

Cheers

Hi all,

Can somebody explain why length("") returns 1 and not 0? How do I test
if a given string is the empty string?
character(0) is not the same as ""
David Winsemius, MD
West Hartford, CT
nchar("")                                                                                                                                                                                  
[1] 0
Hi all,

Can somebody explain why length("") returns 1 and not 0? How do I test
if a given string is the empty string?

Thanks,

Steffen.

	[[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html and provide commented,
minimal, self-contained, reproducible code.
Because it's a character vector with only one element, which just happens to be empty - sort of like why the cardinality of the set { /O } is one. (/O being my best shot at the empty set symbol in plain text). 

You might be thinking of nchar(). 

Michael

Hi all,

Can somebody explain why length("") returns 1 and not 0? How do I test
if a given string is the empty string?

Thanks,

Steffen.

   [[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.