Append data to vector form a column of a dataframe
In addition to Ivan, test$a is not a data.frame anymore but a numerical vector.
class(test$a)
[1] "numeric"
test$a
[1] 1 2 3 So adding a row to your data.frame would be?
rbind(test, 2)
? a 1 1 2 2 3 3 4 2 ? Wolfgang Wu ----- Urspr?ngliche Message ----- Von: Ivan Calandra <ivan.calandra at uni-hamburg.de> An: r-help at r-project.org Cc: Gesendet: 11:19 Mittwoch, 12.Oktober 2011 Betreff: Re: [R] Append data to vector form a column of a dataframe Hi Dom, This is because "3" is recycled. It is necessary because the number of columns have to be the same for every row. Try this instead: c(test$a, 2)? ## you wrote "3" but meant "2" I guess HTH, Ivan Le 10/12/2011 10:47, behave a ?crit :
Dear R-community, When doing this:
test<-data.frame(a=c(1,2,3)) rbind(test$a, 3)
I expect something like:
1 2 3 2
but get:
? ? ? [,1] [,2] [,3] [1,]? ? 1? ? 2? ? 3 [2,]? ? 2? ? 2? ? 2
the same for: rbind(test[["a"]], 2) or rbind(as.vector(test[["a"]]), 2) or rbind(t(as.vector(test[["a"]])), 2) Why is that and how do I extract the "values" from a dataframe to get the desired result? Thank you Dom -- View this message in context: http://r.789695.n4.nabble.com/Append-data-to-vector-form-a-column-of-a-dataframe-tp3897205p3897205.html Sent from the R help mailing list archive at Nabble.com.
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Ivan CALANDRA PhD Student University of Hamburg Biozentrum Grindel und Zoologisches Museum Dept. Mammalogy Martin-Luther-King-Platz 3 D-20146 Hamburg, GERMANY +49(0)40 42838 6231 ivan.calandra at uni-hamburg.de ********** http://www.for771.uni-bonn.de http://webapp5.rrz.uni-hamburg.de/mammals/eng/1525_8_1.php ______________________________________________ R-help at 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.