From antonio.fabio at gmail.com  Sat Nov 24 11:15:45 2007
From: antonio.fabio at gmail.com (Antonio, Fabio Di Narzo)
Date: Sat, 24 Nov 2007 11:15:45 +0100
Subject: [Rd] unexpected result from reshape
Message-ID: <b0808fdc0711240215q570af347p271c48a798bed05a@mail.gmail.com>

Hi all.
I have unexpected reshape results on datasets with certain variable
names. Here a reproducible example:

d <- matrix(seq_len(7*7), 1, 7*7)
vnames <- c('acc','ppeGross','CF','ROA','DeltaSales','invTA','DeltaRevDeltaRec')
varying <- unlist(lapply(vnames, paste, 1:7, sep='.'))
d <- data.frame(d)
names(d) <- varying
d1 <- reshape(d, varying=varying, direction="long")
d[,'ppeGross.2'] == d1[d1$time==2,'ppeGross'] #This is FALSE!
##Try to compare d and d1: values are wrong from the 2nd column

##Changing variable names makes thinks go right:
vnames <- letters[1:7]
varying <- unlist(lapply(vnames, paste, 1:7, sep='.'))
names(d) <- varying
d1 <- reshape(d, varying=varying, direction="long")
d[,'b.2'] == d1[d1$time==2,'b'] #This is TRUE, as expected
##Try to compare d and d1 now: they look right

Any hint on what's wrong here? By now, my workarond is changing
variable names before reshaping, than re-assign old variable names
back after reshape.

Best regards,
Antonio, Fabio Di Narzo.

> R.version
               _
platform       i686-pc-linux-gnu
arch           i686
os             linux-gnu
system         i686, linux-gnu
status
major          2
minor          6.0
year           2007
month          10
day            03
svn rev        43063
language       R
version.string R version 2.6.0 (2007-10-03)



[Rd] unexpected result from reshape
Antonio, Fabio Di Narzo