[gdal-dev] Removing default nodata value from netCDF driver ?

[Even Rouault]

On mardi 5 novembre 2019 14:08:33 CET Julien Demaria wrote:
> Hi Even,
> 
> Thanks for all the work.
> I looked at the new pull request, it seems good but what do you think about
> adding support for case where nc_inq_var_fill() returns no_fill=1? In this
> case the current code uses fillvalue=zero by default (if I'm not wrong)
> which is not ideal, I think it is better to set bGotNoData to false.

I'm not sure to understand well this no_fill concept. My understanding is that 
it is a kind of optimization for the write side. That shouldn't probably 
affect whether we report a nodata value or not ?

> And in
> creation mode do you confirm that it is not possible to create a variable
> without nodata value? 

Yes, except for byte-like datatypes with the change of my pull request

> What do you think about call
> nc_def_var_fill(NC_NOFILL) when creating the band and add a
> nc_def_var_fill(NC_FILL) call in SetNoDataValue()?

Not sure to understand the impact of this. I'd let that to you for another 
pull request.

Even

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