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,                  [EMAIL PROTECTED]
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

______________________________________________
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.

Reply via email to