In a dataframe you call one of the variable (or the column) connecting the name of the column to the dataframe name by means of the $ sign: so z$energy is the column named energy in the dataframe z.
I don't know how to do the same with a multi-variable time-series. I tried both z.energy, z$energy to no avail. What's the right synthax? Ciao Vittorio ______________________________________________ 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
