thanks all!


On Thu, Jul 3, 2014 at 12:38 PM, Peter Langfelder <
peter.langfelder@gmail.com> wrote:

> Precision, precision, precision...
>
> > z[2]-0.15
> [1] 2.775558e-17
>
> My solution:
>
> > z <- signif(seq(.05,.85,by=.1), 5)
> > z[2] - 0.15
> [1] 0
> > z[2]==0.15
> [1] TRUE
>
> Peter
>
> On Thu, Jul 3, 2014 at 11:28 AM, Matthew Keller <mckellercran@gmail.com>
> wrote:
> > Hi all,
> >
> > A bit stumped here.
> >
> > z <- seq(.05,.85,by=.1)
> > z==.05     #good
> > [1]  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
> >
> > z==.15  #huh????
> > [1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
> >
> > More generally:
> >> sum(z==.25)
> > [1] 1
> >> sum(z==.35)
> > [1] 0
> >> sum(z==.45)
> > [1] 1
> >> sum(z==.55)
> > [1] 1
> >> sum(z==.65)
> > [1] 0
> >> sum(z==.75)
> > [1] 0
> >> sum(z==.85)
> > [1] 1
> >
> > Does anyone have any ideas what is going on here?
> >
> >> R.Version()
> > $platform
> > [1] "x86_64-apple-darwin9.8.0"
> >
> > $arch
> > [1] "x86_64"
> >
> > $os
> > [1] "darwin9.8.0"
> >
> > $system
> > [1] "x86_64, darwin9.8.0"
> >
> > $status
> > [1] ""
> >
> > $major
> > [1] "2"
> >
> > $minor
> > [1] "13.1"
> >
> > $year
> > [1] "2011"
> >
> > $month
> > [1] "07"
> >
> > $day
> > [1] "08"
> >
> > $`svn rev`
> > [1] "56322"
> >
> > $language
> > [1] "R"
> >
> > $version.string
> > [1] "R version 2.13.1 (2011-07-08)"
> >
> > --
> > Matthew C Keller
> > Asst. Professor of Psychology
> > University of Colorado at Boulder
> > www.matthewckeller.com
> >
> >         [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help@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.
>



-- 
Matthew C Keller
Asst. Professor of Psychology
University of Colorado at Boulder
www.matthewckeller.com

	[[alternative HTML version deleted]]

