Re: Why is NaN used as extrapolation value?

[David Bateman]

Søren Hauberg wrote:
> 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.
I'm sure some users will find a way to make it incompatible like "(val
== NaN)" for example :-)

D.

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