Please do RTFM, for the help says
df: degrees of freedom (> 0, maybe non-integer). 'df = Inf'
is
allowed. For 'qt' only values of at least one are currently
supported.
On Sun, 12 Oct 2008, Enrico Rossi wrote:
> Sorry about the html-formatted message. Here it is again in plain text.
>
> Hello,
>
> The function qt returns NaN for degrees of freedom <1. For example:
>
>> qt(0.5,0.5)
> [1] NaN
> Warning message:
> In qt(p, df, lower.tail, log.p) : NaNs produced
>
> But qt(0.5,0.5) should be 0, since the distribution is symmetric.
>
>> pt(0,0.5)
> [1] 0.5
>
> It actually fails with any value, as long as df<1.
> Is this a bug, or is there some fundamental reason why this cannot be
> computed?
Neither ....
>
> Thank you,
> Enrico
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
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