Le vendredi 18 novembre 2011 à 16:09 +0100, Jaensch, Steffen [TIBBE] a écrit : > 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