ggplot2 produces error when used in function or S4

Question

I\'ve tough time with ggplot2 when used in function or S4. Here is my code without function:

rm(list=ls(all=TRUE))
library(nlme)
data(Oats)
Data <- Oats

         


        

Answer 1

Your version in the function is missing the following two lines at the very beginning compared to the original version:

Data$Env <- factor(Data$Block)
Data$Gen  <- factor(Data$Variety)

Have you experimented with using debug() to step through functions to find the source of errors?