2 messages · wolfram at fischer-zim.ch, Peter Dalgaard
[R 2.0.0 on Linux] I tried:
df <- data.frame(
grp1=factor( c('A' ,'A' ,'A' ,'D', 'D' ) ) ,
grp2=factor( c('a1','a2','a2','d1','d1') )
)
df
grp1 grp2 val 1 A a1 1 2 A a2 2 3 A a2 4 4 D d1 8 5 D d1 16 I got:
with( df, ave( val, grp1, grp2, FUN=sum ) )
[1] 1 24 24 NA NA I have expected to get: [1] 1 6 24 Do I misunderstand something with `ave' or is there a bug? Thanks - Wolfram
Wolfram Fischer <wolfram at fischer-zim.ch> writes:
[R 2.0.0 on Linux] I tried:
df <- data.frame(
grp1=factor( c('A' ,'A' ,'A' ,'D', 'D' ) ) ,
grp2=factor( c('a1','a2','a2','d1','d1') )
)
df
grp1 grp2 val 1 A a1 1 2 A a2 2 3 A a2 4 4 D d1 8 5 D d1 16 I got:
with( df, ave( val, grp1, grp2, FUN=sum ) )
[1] 1 24 24 NA NA I have expected to get: [1] 1 6 24 Do I misunderstand something with `ave' or is there a bug?
Both. You should have expected 1 6 6 24 24. Apparently the culprit is this line inside ave() unlist(lapply(split(x, g), FUN))[g] which acts up if there are empty levels of g. It works with unlist(lapply(split(x, g), FUN))[as.character(g)] but that doesn't strike me as the right solution.
O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907