[Rd] Binning of integers with hist() function odd results (PR#14046)

From: <gug_at_fnal.gov>
Date: Sat, 07 Nov 2009 00:30:12 +0100 (CET)


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).



R-devel_at_r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel Received on Sat 07 Nov 2009 - 13:32:06 GMT

This archive was generated by hypermail 2.2.0 : Sun 08 Nov 2009 - 09:30:21 GMT