20:01:21 <RRSAgent> RRSAgent has joined #sdwcov
20:01:21 <RRSAgent> logging to http://www.w3.org/2016/03/23-sdwcov-irc
20:01:23 <trackbot> RRSAgent, make logs world
20:01:23 <Zakim> Zakim has joined #sdwcov
20:01:25 <trackbot> Zakim, this will be SDW
20:01:25 <Zakim> I do not see a conference matching that name scheduled within the next hour, trackbot
20:01:25 <phila> present+ phila
20:01:26 <trackbot> Meeting: Spatial Data on the Web Working Group Teleconference
20:01:26 <trackbot> Date: 23 March 2016
20:01:38 <phila> RRSAgent, make logs public
20:01:42 <jtandy> zakim, code?
20:01:43 <Zakim> I have been told this is SDW Coverages https://mit.webex.com/mit/j.php?MTID=mfd4c5a8f42f6d4063eb4a40a7d0c3d36 pw is v4qtEh56 OR dial +1-617-324-0000, access code 642 235 291
20:01:56 <kerry> Meeting: SDW coverages
20:02:02 <eparsons> eparsons has joined #sdwcov
20:02:06 <phila> issue-1?
20:02:06 <trackbot> issue-1 -- Blah blah test -- closed
20:02:06 <trackbot> http://www.w3.org/2015/spatial/track/issues/1
20:02:15 <jtandy> present+ jtandy
20:02:30 <eparsons> present+ eparsons
20:02:41 <billroberts> regrets+ jon.blower
20:02:46 <billroberts> regrets+ maik.riechert
20:04:30 <kerry> present + kerry
20:04:36 <phila> RRSAgent, draft minutes
20:04:36 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
20:04:36 <billroberts> present+ billroberts
20:04:37 <kerry> present+ kerry
20:04:39 <ScottSimmons> present+ ScottSimmons
20:04:41 <sam_t> present+ sam_t
20:04:43 <dmitrybrizhinev> present+ dmitrybrizhinev
20:04:47 <phila> RRSAgent, draft minutes
20:04:47 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
20:05:31 <phila> present+ Newton, BernadetteLoscio
20:05:38 <phila> chair: Bill
20:06:24 <kerry> scribe: kerry
20:06:33 <kerry> scribeNick: Kerry
20:06:41 <billroberts> https://www.w3.org/2016/03/09-sdwcov-minutes
20:07:00 <phila> PROPOSED: Accept last week's mintes
20:07:09 <phila> s/mintes/minutes
20:07:09 <billroberts> +1
20:07:15 <jtandy> +1
20:07:21 <eparsons> +0 Not there
20:07:29 <kerry> Proposed: accept last weeks minutes  https://www.w3.org/2016/03/09-sdwcov-minutes
20:07:34 <kerry> +1
20:07:54 <phila> +1
20:08:13 <phila> RESOLVED: Accept last week's minutes
20:08:19 <billroberts> https://www.w3.org/2015/spatial/wiki/Patent_Call
20:08:23 <phila> RRSAgent, draft minutes
20:08:23 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
20:08:55 <billroberts> https://www.w3.org/2015/spatial/wiki/Meetings:Coverage-Telecon20160323
20:09:06 <kerry> topic: Review of use cases
20:09:38 <kerry> topic: welcome to editor Maik Reichert
20:10:02 <kerry> topic: topic: Review of use cases (action)
20:10:13 <billroberts> https://www.w3.org/2015/spatial/wiki/Coverage_UCR_notes
20:11:17 <kerry> billroberts: at bottom in summary see that subsetting came out a lot
20:11:45 <kerry> ...assign an identifier to a subset of a coverage of a dataset
20:12:12 <kerry> ....also for provenance so you can point to how the processing happened
20:12:51 <kerry> ...the question of delivering a full coverage is a special case of delivering a subset -- if we address addressing and formatting it will be solved
20:13:10 <kerry> ...also some use cases for poihnt cloud and time series -- need to keep these in mind
20:13:42 <kerry> ...also note that the region of interest might be complicated, not just a bounding box, may be polygon or tunnel underground
20:13:57 <kerry> ... any comments?
20:14:16 <kerry> jtandy: they are the things I can recall
20:15:16 <kerry> phila: note the way subsetting tumbles out becuase we are struggling in dwbp to say something that is *not* spatailly-specific
20:15:35 <kerry> ....dwbp does not have good use cases for this
20:15:36 <jtandy> q+ to query predefined subsets or on-the-fly query
20:15:58 <kerry> billroberts:  also we have time subsets and variable subsets
20:16:04 <kerry> +q
20:16:19 <billroberts> ack jtandy
20:16:20 <Zakim> jtandy, you wanted to query predefined subsets or on-the-fly query
20:16:45 <eparsons> jtandy
20:17:18 <kerry> jtandy: we had a long email thread on subsetting for BP
20:17:43 <kerry> ... one kind is subsetting for useful chunks to be manageable (a predefined set)
20:18:00 <kerry> ... other kind is an on-the-fly query chunk
20:18:04 <kerry> ...we need both
20:18:31 <kerry> ...rdf datacube does predefined type but not query type
20:19:09 <kerry> billroberts:  datacube can be used for query-type but perhaps less flexible
20:19:37 <kerry> jtandy: when i assign an identifier to a subset it could be anythinh
20:19:44 <billroberts> ack kerry
20:19:52 <kerry> ...but a query type identifier is also an api, effectively
20:20:21 <phila> kerry: I hate us calling it subsettingm given all the different dimensions that we need to talk about
20:20:33 <phila> s/subsettingm/subsetting/
20:20:39 <phila> q+
20:20:46 <billroberts> ack phila
20:20:53 <kerry> kerry;' does not like "subsetting"
20:22:01 <phila> s/kerry;' does not like "subsetting"/kerry: does not like "subsetting"
20:22:26 <phila> Discussion between phila and kerry about whether audience for Coverages doc is only spatial folks
20:22:37 <phila> kerry: How about 'sub coverage?'
20:22:42 <phila> billroberts: That makes sense to me
20:23:00 <phila> phila: Doesn't like 'sub coverage'
20:23:08 <kerry> action: kerry to present some suggestions for renaming "subsetting"
20:23:08 <trackbot> Created ACTION-152 - Present some suggestions for renaming "subsetting" [on Kerry Taylor - due 2016-03-30].
20:23:37 <BernadetteLoscio> yes!
20:23:41 <billroberts> http://w3c.github.io/dwbp/bp.html#EnableDataSubsetting
20:23:44 <kerry> topic: DWBP subsetting
20:24:19 <kerry> BernadetteLoscio: we have a proposal as in the irc, but it is difficult to test
20:24:54 <kerry> ... it is generic and important but there are different approaches
20:25:01 <kerry> ...e.g. apis, queries
20:25:24 <kerry> ... we are not sure ehther we should have this as a bp or to just describe it
20:25:35 <kerry> ...what would be helpful to you and how would it be testable?
20:25:42 <phila> s/ehther/whether/
20:25:44 <jtandy> q+ to ask if you could cover 'subsetting' as an example operation in your API
20:25:55 <billroberts> ack jtandy
20:25:55 <Zakim> jtandy, you wanted to ask if you could cover 'subsetting' as an example operation in your API
20:26:50 <kerry> jtandy: when I look at subsetting I think it is one example of the way you could work with data... there are other BP about offering an API in DWBP
20:27:27 <kerry> ... data subsetting makes a lot of sesne for slices for statistical, etc, but when I look more generically it is really just an operation you provie thru an API
20:27:50 <kerry> ...could be just an illustrative example
20:27:54 <BernadetteLoscio> q+
20:28:08 <billroberts> ack BernadetteLosci
20:28:14 <kerry> ...but it makes a lot of sense for time series and satellite data (somehow differently)
20:28:30 <kerry> billroberts: should we also talk about subsetting for download
20:29:05 <kerry> jtandy: you should also talk about the data you take away after downloading
20:29:34 <kerry> ...I would suggest when working with large datasets a typical use case would be an api to select parts of that dataset
20:30:04 <kerry> ...difficult for you to reference what we do, but I suggest just describe an illustrative example of a convenience API
20:30:30 <kerry> s/billroberts/bernadette:
20:30:55 <kerry> BernadetteLoscio: perhaps we can talk about subsetting along with downloads as another example
20:31:30 <kerry> billroberts: the problem with api/query is that it is futile to specify upfront what it should look like in general
20:32:01 <kerry> ... maybe all we can do is say "you need an API" or esle we end up inventing yet another query language
20:32:14 <kerry> ...needs to be up to the data provider
20:32:19 <kerry> jtandy: agrees
20:32:21 <phila> q+
20:32:27 <billroberts> ack phila
20:33:07 <kerry> phila: <moved us with his absent speech>
20:33:11 <phila> phila: Requirement no. 1 can assign an identifier to a subset of a coverage dataset
20:33:58 <kerry> ... we have been saying "you just give it a uri", although a uri *is* an api
20:34:46 <kerry> ...for bulk download is it useful to say you can use the api and you can give it an aexample of its own, e.g. meteorological data for the last week
20:34:53 <jtandy> q+
20:34:57 <kerry> ...should this go in dwbp or sdw?
20:35:10 <kerry> s/aex/ex/
20:35:50 <kerry> phila:  should dwbp do this ... your first ucr says you need to asign an identifier to a subset
20:35:55 <billroberts> ack jtandy
20:36:00 <kerry> billroberts: yes it would be useful
20:36:46 <kerry> jtandy: it makes sense to for dwbp to provide some advice -- if you have data that is too big for a web application then providew a mechanism to get hold of bits of it
20:37:06 <kerry> ...eg. using predefined slices or an API
20:37:26 <kerry> ...test by "here is a massive dataset -- can you work with it in a browser app?
20:38:07 <kerry> billroberts: use cases where this emerged was wanting to attach some metadata to it, sometiomhsd that is the full set, not a subset
20:38:39 <phila> is that helpful newton_dwbp?
20:38:44 <kerry> s/sometiomhsd/something/
20:39:13 <newton_dwbp> I liked jtandy point
20:39:21 <kerry> billroberts: need to look again at email thread on this, any otehr comments?
20:39:30 <BernadetteLoscio> q+
20:39:32 <newton_dwbp> q+
20:39:37 <newton_dwbp> q-
20:39:47 <billroberts> ack Be
20:40:09 <kerry> BernadetteLoscio: we like jtandy's idea and will bring to our dwbp discussion. thank you very much
20:40:51 <kerry> topic: RDF datacube action
20:41:19 <kerry> billroberts: which aspects of rdf datacube would be good for defining subsets?
20:41:25 <dmitrybrizhinev> q+
20:41:46 <jtandy> q+ to note qb:slice
20:41:55 <billroberts> ack jt
20:41:55 <Zakim> jtandy, you wanted to note qb:slice
20:42:00 <kerry> .... bill will write note on pros and con of datacube and mechanisms that would be helpful for subsets
20:42:04 <billroberts> ack dmitrybrizhinev
20:42:10 <kerry> dmitrybrizhinev:
20:42:44 <kerry> dmitrybrizhinev:  we are a group of students working on an example implementation for coverages, we are worried about verbosity of datacube
20:43:19 <kerry> ...flipside is taking a subset with lots of granularity with a sparql query is useful butused verbose
20:44:01 <kerry> ...i have been converting the coveragesjson to rdf but this is the query... is there a best of bost worlds
20:44:29 <kerry> s/bost/both/
20:44:49 <kerry> billroberts: please share anything written up
20:45:20 <kerry> jtandy: agree about way too verbose, jonblower keeps saying this cannot be used to carry the data, but the metadata might be useful
20:45:39 <jtandy> https://www.w3.org/TR/vocab-data-cube/#slices
20:45:47 <kerry> ... for describing subsets there is qp:slice and also a mechanism for creating arbitrary groups in the spec
20:46:25 <kerry> .... leaving the data in a desne array is arguable no different to the way we deal with goespatail stuff all the time, eg geometry objeects in WKT or in GML
20:46:54 <kerry> ...becuase we want to treat the whole geometry as an object (we don't break it up), the same can apply to a dense array of data
20:47:56 <kerry> ... in the same way the geosparql can provide operations on data, when we are working with coverage data in a webby form we ned to provide some additional mechanism for querying inside
20:49:08 <kerry> billroberts: e.g.75th point of array needs to be accessible, and you need some coordinates that stick with the points... that kind of conciseness is needed for whole grid but when there are only bits it may work well
20:49:25 <kerry> ...datacube couldwork weel itself for a small subset if not the entire grid
20:49:32 <kerry> s/weel/well/
20:49:53 <kerry> jtandy: if you just want ith column and jth row ...
20:50:00 <kerry> q+
20:50:04 <billroberts> ack kerry
20:50:28 <phila> kerry: were you suggesting, Bill, that the QB model could be used as a response format for a query over a bigger set
20:50:49 <phila> billroberts: Not precisely, but that structure of an observation
20:51:20 <phila> ... If you just have one data point, you need all the dimensional info and the metadata. Some metadata applies to the whole dataset, some to a specific point.
20:52:05 <phila> ... If you have a grid, you don't need all the coords 'cos you can work them out but a point cloud does need them.
20:52:27 <kerry> billroberts:  the structure of an observation is very useful for datacube way
20:52:51 <kerry> jtandy: index space querying , natural coord subsetting, more work to do here...
20:52:54 <phila> q+
20:52:59 <billroberts> ack phila
20:53:24 <kerry> phila: what proportion of coverage data is on a regular grid?
20:53:48 <kerry> ... I am thinking of those with only 2 or 3 lines with regular definition and you can work the rest out
20:54:12 <jtandy> q+ to respond to phila's question about regular grids
20:54:13 <kerry> ...in such cases a template uri could be generated that does identifiy a "slice"
20:54:37 <kerry> ..so we could say "of you have a regualr grid pattenr this is how you generate the uri template"
20:54:46 <kerry> s/pattnr/
20:54:51 <billroberts> ack jt
20:54:51 <Zakim> jtandy, you wanted to respond to phila's question about regular grids
20:54:59 <eparsons> q+
20:55:28 <kerry> jtandy: yes it is a large fraction by volume and number of datasets, eg satellite imagery,
20:56:35 <billroberts> ack eparsons
20:56:56 <kerry> ..but there are other important cases such as in-situ observations by radiospondes or buoys or gliders irregualr coverages happen more (like opendap/netcdf index-based subsetting)
20:57:14 <jtandy> s/irregualr/irregular/
20:57:31 <phila> RRSAgent, draft minutes
20:57:31 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
20:57:46 <kerry> eparsons: aggrees. my meta-question is , where is the stuff with a more semantic approach -- are we just reinventing the wheel of tools in other places?
20:58:35 <kerry> jtandy: phil had said data is easy, metadata is challenge. the metadata is the bit to get the advantage of linked data such as what you are measuring etc
20:59:05 <kerry> ...metadata as linked data is key, then something else for dense arrays of data
20:59:27 <kerry> eparsons: so lets not get worked up on data size then as ther are other appoaches
20:59:43 <jtandy> s/appoaches/approaches/
21:00:02 <kerry> billroberts: index array of data is good approah for some stuff, but we need to think harder about others
21:00:17 <phila> Topic: Jermey Stole our time slot
21:00:18 <kerry> billroberts: jeremy stole out timeslot
21:00:30 <phila> s/Jermey/Jeremy
21:00:42 <kerry> ... we had been proposing to follow the main group for time changes
21:00:53 <kerry> topic: meeting times
21:01:08 <kerry> kerry: kick them off!
21:01:39 <kerry> s/Jermey/Jeremy/
21:02:04 <phila> May I suggest a Doodle poll?
21:02:28 <kerry> billroberts: moans about "the australian issue"
21:02:55 <kerry> +1 to bill's idea
21:03:51 <phila> 16:00 CEST, 15:00 BST etc.
21:04:07 <kerry> billroberts: meeting close
21:04:12 <phila> RRSAgent, draft minutes
21:04:12 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
21:04:13 <kerry> rrsagent, draft minutes
21:04:13 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html kerry
21:04:26 <billroberts> bye everyone
21:04:33 <phila> RRSAgent, draft minutes
21:04:33 <RRSAgent> I have made the request to generate http://www.w3.org/2016/03/23-sdwcov-minutes.html phila
21:04:45 <newton_dwbp> bye
22:07:49 <billroberts> billroberts has joined #sdwcov