[R] density(x)

[Christoph Hanck]

Dear experts, 

when trying to estimate an kernel density function with density(x) I get the following 
error message with imported data from either EXCEL or text files:

Error in density(spr) : argument must be numeric.

Other procedues such as truehist work. If I generate data within R density works fine. 
Does anybody have an idea?

Yours
--
Christoph Hanck
Wissenschaftliche Hilfskraft
Lehrstuhl für Empirische Wirtschaftsforschung, Prof. Dr. Wilfling
http://www.wiwi.uni-muenster.de/~05/
WWU Muenster
Tel.: +49-251-83 25043
eMail: 05chha at wiwi.uni-muenster.de