On Sat, 8 Oct 2005, nawaf b wrote: > Hi - > > I was wondering if anyone came across a problem such as mine! I was trying > to create a user-defined function, however, the results from calling the > function are unexpected! > > When passing X parameter as a single value variable (x<-c(3)), everything > works fine. However, when passing a parameter as a vector with multiple > values (as the case in my code), the 'if condition' is only executed once! > > Here is my code: > > x > [1] 0.3 1.0 0.7 22.0 > > myfunction<-function(x) > + { > + if (x>=1) 0 > + else x^2 > + } > > myfunction(x) > [1] 0.09 1.00 0.49 484.00 > Warning message: > the condition has length > 1 and only the first element will be used in: if > (x >= 1) 0 else x^2 > > > > Is there a way to overcome this issue? Can you please explain what > modifications to the code I need to accommodate to make it work.
> myfunction<-function(x) + ifelse(x>=1, 0, x^2) > x <- c(0.3, 1.0, 0.7, 22.0) > myfunction(x) [1] 0.09 0.00 0.49 0.00 ifelse() is vectorised, but if() only looks at the first element in x before deciding what to do - so if the condition is longer, the rest gets ignored. > > Thanks, > > Nawaf > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > -- Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: [EMAIL PROTECTED] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html