[PROJ] Big grid files - side tracking the conversation

[Javier Jimenez Shaw]

On Mon, 28 Apr 2025 at 13:35, Mircea Neacsu <mircea at neacsu.net> wrote:

> Apologies for my side tracking:
>
> >During the summit I asked about the interpolation method. The metadata
> says that it should be biquadratic. The answer was: "for the undulation
> there is almost no difference.
> > But for other magnitudes, like vertical deflection, it is more
> noticeable. However, to match our values you have to do biquadratic
> interpolation"
>
>
> Do you know any reason, apart from historical ones, to use the biquadratic
> interpolation? I did a short writeup on different interpolation methods
> <https://neacsu.net/docs/programming/2d-interpolation-functions/> and,
> from what I can see, the biquadratic method is the worst possible one.
>
>
No, I do not know the reason. I asked my contact in the summit. I will
share the answer if I get any.

There is people from the NOAA subscribed to this mailing list. They are
usually quiet ;)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/proj/attachments/20250428/ba653224/attachment.htm>