Hi On 4 Sep 2003 at 14:35, Ulrich Leopold wrote:
> > E.g., > > > > mydata$difference <- mydata$x - mydata$y > > > > That's what I thought, but I get the following message: > > > propLSK.STONE.Pox0t30$Pox0t30STONE-propLSK.STONE.Pox0t30$Pox0t30 > numeric(0) Beware of case sensitivity propLSK.STONE.Pox0t30$Pox0t30stone-propLSK.STONE.Pox0t30$Pox0t30 shall work as expected A little bit less complicated names of data frames and variables could be more readable and more error prone. Cheers Petr > > Does it mean the resulting vector is empty? If yes, what could be the > reason for it? Both columns are available: > > UGreen Pox0t30 Pox0t30Stone > 1 0 37.150000 16.461500 > 2 0 6.833330 7.464404 > 3 0 9.750000 15.616870 > 4 0 15.050000 19.146500 > 5 0 13.266700 10.515750 > 6 0 34.300000 27.304840 > 7 0 45.800000 27.217171 > 8 NA 23.200000 16.844601 > 9 0 13.600000 28.051821 > 10 0 16.750000 6.021914 > 11 0 16.433300 3.832123 > 12 0 17.333300 3.905555 > > > What am I missing? > > Ulrich > > > -- > __________________________________________________ > > Ulrich Leopold MSc. > > Department of Physical Geography > Institute for Biodiversity and Ecosystem Dynamics > Faculty of Science > University of Amsterdam > Nieuwe Achtergracht 166 > NL-1018WV Amsterdam > > Phone: +31 20 525 7456 (7451 Secretary) > Fax: +31 20 525 7431 > Mobile: +31 64 220 3028 > Email: [EMAIL PROTECTED] > URL: www.science.uva.nl/ibed/research/Research_Fields/fg/sta fffg/index > .html > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help Petr Pikal [EMAIL PROTECTED] ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help