[CF-metadata] attributes for min/max data values for visualization

[Jon Blower]

Hi Phil,

>  { minimum_data_value, maximum_data_value }, or
>  { minimum_variable_value, maximum_variable_value }

Thanks for this suggestion - both of these look sensible to me.  Are
there any other analogous features of CF that might give guidance
here?

Cheers, Jon

On 3/28/07, Philip Bentley <philip.bentley at metoffice.gov.uk> wrote:
>
>  Hi Jon et al,
>
>  IMO, this idea seems commendable for actual min/max data values. However,
> is there merit in adopting somewhat more specific, albeit longer, attribute
> names? I'm thinking of the situation - contrived perhaps - wherein a
> non-CF-savvy end-user of a netCDF file sees a metadata attribute called
> "value_min" and asks the question "Minimum value of what?".
>
>  Perhaps the answer is self-evident from context; that is, since the
> attribute is attached (in the netCDF header) to the variable it describes
> then the association is clear. But in a client software application that
> association might not be so obvious.
>
>  In which case is it worth considering more verbose, but more descriptive
> attribute names, e.g.
>
>  { minimum_data_value, maximum_data_value }, or
>  { minimum_variable_value, maximum_variable_value }
>
>  Just a suggestion!
>
>  Regards,
>
>  Phil
>
>  On Wed, 2007-03-28 at 14:00 +0100, Jon Blower wrote:
>  Dear Jonathan and list,
>
> Just to re-start this debate. The original question was whether there
> was (or could be) a pair of CF attributes to identify the min and max
> data values in a CF dataset for the purposes of aiding visualization
> tools to choose sensible colour scales.
>
>
>  <snip>
>  These attributes would be optional, but easy to add to existing
> datasets, either through editing the NetCDF files or through other
> decorators such as NcML, CDML etc.
>
> I propose calling these attributes value_min and value_max.
>
> What do others think? Is this a sensible addition to CF?
>
> Jon
>
>
>


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