[CF-metadata] use of _FillValue vs valid_range, and minimum and maximum

From: Schultz, Martin <m.schultz>
Date: Thu, 23 May 2013 15:10:44 +0000

> >... but computing min & max on the fly can also be very expensive.
> >We have aggregated model output datasets where each variable is more
> >than 1TB!

> Sure, I can see that that's useful metadata about the dataset, and that
> there's value in caching it somewhere. I just don't think it belongs with
> the metadata inside the netcdf file. What's the use case for storing it
> there?

Dear all,

      that may be an issue of "style", or more technically speaking the way you set-up your system(s). I do think there is use for this as soon as you take a file out of an interoperable context. However, it's a very good and valid point to say that this information can (very) easily get corrupted. Thus it may be good to define some way of marking "fragile" metadata (i.e. metadata that can be corrupted by slicing or aggregating data from a file -- maybe even from several files). In fact this is related to the issue of tracking metadata information in the data model -- that has been brought up in the track ticket but was referred to the implementation...

Cheers,

Martin




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Received on Thu May 23 2013 - 09:10:44 BST