- From: Karen Coyle <kcoyle@kcoyle.net>
- Date: Thu, 6 May 2021 09:08:56 -0700
- To: Andrea Perego <ndr.prg@gmail.com>
- Cc: W3C DX WG - Public <public-dxwg-wg@w3.org>
Andrea, I chatted with Tom Baker and we have agreed that we need to do some better examples, ones that look more like "real data" than the mock-ups we have in the primer now. Hopefully the next version of the documentation will be clearer in terms of shapes with better examples. Thanks again for your comments - this is what helps us improve! kc On 5/1/21 2:33 PM, Karen Coyle wrote: > Andrea, > > "Shape" is something that we've struggled with,[1] and I'll pass along > your comments. It really is a node in RDF. The node often (but not > always) represents an entity in the metadata, like "person" or > "address", that gets described by properties. One way to think of it is > that the shape is an organizer for a group of properties. In SHACL terms > the TAP shape is most likely a target node. > > An example (a very simple one) would be useful here I think. Here's a > shape with two properties: > > Bookshape > dc:title > dct:creator > > which could describe metadata that looks like: > > <http://example.com/book123456> > dc:title "DC TAP" ; > dct:creator "Andrea". > > Is some of the confusion from the fact that the shape is on the same row > with the properties? In TAP, the shapeID is a value in a column for each > of the properties for that shape: > > Bookshape | dc:title > Bookshape | dct:creator > > which says that properties dc:title and dct:creator are part of the > Bookshape shape. (Some prefer not repeating the shapeID on each row > because it is easier to read, and will assume that programs processing > the CSV will read the blank cell as "same as above", much like Open > Refine or other tools.) > > There has also been a request that shapes be on their own row, which > would allow you to express, for example, cardinality for the shape > itself. So you would have: > > Bookshape | (mandatory=true) > Bookshape | dc:title > Bookshape | dct:creator > > or > > Bookshape | (mandatory=true) > | dc:title > | dct:creator > > However, we had trouble fitting that into a standard CSV without adding > many more columns, e.g. cardinality columns for shapes could be > functionally different from cardinality columns for properties. It is > possible we were being too perfectionist, but that's how it worked out. > Although not (yet) set in stone. > > I'm totally available to chat if anyone wants to. Some of this is hard > to do in email. And I will pass along your comments to the group. > > kc > [1] https://github.com/dcmi/dcap/issues/73 > > On 4/29/21 2:25 PM, Andrea Perego wrote: >> Thanks a lot for the heads up, Karen! >> >> Reading the documents, there is a point not completely clear to me, >> namely, what a "shape" is intended to be in DC TAP - in particular, >> when applied to an RDF vocabulary. Is it a class (in the RDF sense)? a >> constraint (in the SHACL sense)? both? >> >> I think one of the reasons for my confusion concerns the examples, >> where shapes are denoted by literals (courses, tutors, etc.), whereas >> properties by IRIs from vocabularies as Dublin Core, FOAF, etc. >> >> Andrea >> >> On Thu, Apr 29, 2021 at 8:13 PM Karen Coyle <kcoyle@kcoyle.net> wrote: >>> >>> All, >>> >>> I wanted to let you know that the Dublin Core Tabular Application >>> Profiles specification is now a draft [1] on the DC site, and there is a >>> blog post with additional information and links. [2] >>> >>> We think that this draft is fairly stable, but we are now working on >>> various extensions including a manifest. The manifest document will not >>> be a single solution but examples of various ways that additional >>> information about the table can be expressed. >>> >>> What may be of interest to this group in that regard is that once we've >>> gotten further on our ideas for a manifest we intend to analyze >>> compatibility with the PROF vocabulary, and with the JSON context of CSV >>> on the web.[3] >>> >>> I also intend to try encoding DCAT-AP in TAP, although it is dauntingly >>> large so I may just do a portion. In any case, I'll get back to you when >>> I have more to report. >>> >>> Thanks, >>> >>> kc >>> >>> [1] >>> https://www.dublincore.org/groups/application_profiles_ig/dctap_primer/ >>> >>> [2] https://www.dublincore.org/blog/2021/draft_tap_specification/ >>> >>> [3] https://www.w3.org/TR/tabular-data-primer/#handling-language-in-csvs >>> >>> -- >>> Karen Coyle >>> kcoyle@kcoyle.net >>> http://kcoyle.net >>> >>> >> > -- Karen Coyle kcoyle@kcoyle.net http://kcoyle.net
Received on Thursday, 6 May 2021 16:10:58 UTC