g...@fnal.gov wrote:
Full_Name: Gerald Guglielmo
Version: 2.8.1 (2008-12-22)
OS: OSX Leopard
Submission from: (NULL) (131.225.103.35)
When I attempt to use the hist() function to bin integers the behavior seems
very odd as the bin boundary seems inconsistent across the various bins. For
some bins the upper boundary includes the next integer value, while in others it
does not. If I add 0.1 to every value, then the hist() binning behavior is what
I would normally expect.
h1<-hist(c(1,2,2,3,3,3,4,4,4,4,5,5,5,5,5))
h1$mids
[1] 1.5 2.5 3.5 4.5
h1$counts
[1] 3 3 4 5
h2<-hist(c(1.1,2.1,2.1,3.1,3.1,3.1,4.1,4.1,4.1,4.1,5.1,5.1,5.1,5.1,5.1))
h2$mids
[1] 1.5 2.5 3.5 4.5 5.5
h2$counts
[1] 1 2 3 4 5
Naively I would have expected the same distribution of counts in the two cases,
but clearly that is not happening. This is a simple example to illustrate the
behavior, originally I noticed this while binning a large data sample where I
had set the breaks=c(0,24,1).
This is as documented. See the include.lowest argument. Annoying, but
not a bug.
(It is arguably a design error that hist() is looking for "pretty"
breakpoints rather than pretty midpoints, or maybe something more
advanced to handle cases where the data are effectively tied to a
lattice. It's been around "forever", though.)
--
O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B
c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K
(*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalga...@biostat.ku.dk) FAX: (+45) 35327907
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
