Dear R users, I wrote the following toy example to explain my problem :
a=0 f=function(x,y,z) { if (a==0) x[1]+x[2]+y if (a!=0) x[1]+x[2]+y+z } f(1:2,3) I have not specified z and I get an error. Although a=0, R seems to want to know z because it's in the expression x[1]+x[2]+y+z. So I tried to put a default value : a=0 f=function(x,y,z=0) { if (a==0) x[1]+x[2]+y if (a!=0) x[1]+x[2]+y+z } f(1:2,3) Why isn't it working ? Sometimes everything is fine even though a parameter is not specified. Thanks a lot. [[alternative HTML version deleted]] ______________________________________________ R-help@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.