Re: Why is NaN used as extrapolation value?

[Søren Hauberg]

David Bateman skrev:
> Søren Hauberg wrote:
> > Hi,
> >   The current interpolation functions all use NaN as extrapolation
> > value. I know that Matlab does this, which (I guess) is why we do it.
> > But since we have NA why isn't that used? Using NA as default
> > extrapolation value should be Matlab compatible (right?) and would
> > IMHO make more sense.
> >
> > Søren
> >
> > P.S. Since I brought it up I'll be happy to send patches if requested
> > (they should be damn easy to produce...)
> Yes I believe the only reason is compatibility. However I wouldn't
> change it. The user can always specify the extrapval if they want it to
> be NA, and changing it will only cause additional bug reports of matlab
> incompatibility.
Would this cause incompatibilities? I mean, 'isnan(NA)' produces 'true' 
since 'NA' is a NaN.

Søren