Sounding Datum meta feature in any TDS?

[MikusRL]

I am working on the test dataset (TDS) upgrading to 1.2 version. Started with the No6 dataset, as was appointed by @TomRichardson6 . I use CARIS, and it still asks to input sounding datum in the metadata of a CARIS project. I guess it could help automate Sounding Datum feature creation while in production, as it is no longer needed in S-101 metadata, but I actually could not find which is the Sounding Datums Vertical Datum attribute value, also not in the No3 TDS. I assume it would need to be used the same across all the TDS, or is it ok to be different from TDS to TDS?  Happy to hear your views, as almost all TDS has some kind of depth related feature in them, hence we need to add the Sounding Datum feature as well in each of those TDS, as it is a mandatory meta feature for a legal S-101 v1.2, correct? Thanks. @kusala9 Jonathan, your thoughts?

[kusala9]

I can add Vertical Datum of Data and Sounding Datum to all the TDS if that would help. They can just be added as features, and linked to the Data Coverage features. The VDAT in the headers aren't used at all now (that's my understanding). If that works for everyone I can do that before any further changes are made to the datasets - if @TomRichardson6 is ok with that just let me know..

which datums to use? I'm not sure... Let me know what would work, I guess LAT probably for soundings....

[DavidGrant-NIWC]

which datums to use?

Recommend LAT and MLLW for soundings since those are both widely used. Perhaps MHWS and HAT for vertical datums.

[kusala9]

I've just pushed updates to all the cells, which takes them to edition 4 and adds sounding datum and vertical datum of data to every cell. Uses LAT and MHWS respectively for SDAT/VDAT. Can be changed if they don't work, new features validate ok and work in latest viewer.

[kusala9]

is there value in mixing things up for these cells? They can be changed. You can see the changes in the .yaml files:

https://github.com/iho-ohi/S-101-Test-Datasets/commit/3c5d13fe34d821f55c2f64054bd22ca0b13c63aa#diff-c67cff60f2e4104bb74012945167831b4578f06b0ae7fbe019c4f24ea65d2545

[MikusRL]

My opinion would be that for these type and purpose of the test datasets it would be good to have the mandatory meta features harmonized, which includes the feature Sounding Datum. But in the No3 TDS there could be perhaps more expanded and captured these features to cover the notes from the DCEG (3.9.1). But it is just my thoughts.

[DavidGrant-NIWC]

DS3 doesn't have full coverage for vertical datum of data. I think the value in having at least one dataset with multiple values (DS3) is to test:

• The legend
• Hierarchy of metadata
• WLA

Testing meta-features requires the addition of features which override and inherit the value populated in the meta-feature.

[kusala9]

ah, my mix up - I missed the multiple data coverage features in DS3. Corrected and made an edition 5 so the two DataCoverage features have different datum settigns (as per the suggestions in the previous comment). This now provides full cover across the cell. We can discuss at the TDS meeting on Monday as well.

https://github.com/iho-ohi/S-101-Test-Datasets/commit/df953f76a2c7ac090a143b7d4bb85fb8d5b88f05

[DavidGrant-NIWC]

Looks good, but I'd still recommend adding some individual features which both override and inherit from the meta-features.

[kusala9]

agree. one for the TDS meeting on Monday. I'll bring it up.

[kusala9]

New features with vertical datums are in progress for the datasets. Suggest we track with this issue.

[kusala9]

all done. This can probably be closed now.

[DavidGrant-NIWC]

but I'd still recommend adding some individual features which both override and inherit from the meta-features.

Not seeing this change. Should I add a new issue and close this one?

[kusala9]

agree - leave this open, we'll track the addition of new features which override the datums.