Changes between Version 19 and Version 20 of PetascopeTimeHandling


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Timestamp:
Jul 9, 2015 4:33:44 PM (21 months ago)
Author:
pbaumann
Comment:

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  • PetascopeTimeHandling

    v19 v20  
    1919An optional time zone expression may be added at the end of the value. The letter `Z` is used to indicate Coordinated Universal Time (UTC). All other time zones are represented by their difference from Coordinated Universal Time in the format `+hh:mm`, or `-hh:mm`. These values may range from `-14:00` to `14:00`. For example, US Eastern Standard Time, which is five hours behind UTC, is represented as `-05:00`. If no time zone value is present, it is considered unknown; it is not assumed to be UTC.''
    2020
    21 At the time being, [http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/ we provide] a first basic set of Temporal CRSs (T-CRSs) which (among others) are under review process by the OGC-NA authority and represents part of the effort of the newly born (public) OGC [http://external.opengeospatial.org/twiki_public/TemporalDWG/WebHome Temporal Domain Working Group]. These definitions are:
     21At the time being, [http://rasdaman.org:8080/def/crs/OGC/0/ we provide] a first basic set of Temporal CRSs (T-CRSs) which (among others) are under review process by the OGC-NA authority and represents part of the effort of the newly born (public) OGC [http://external.opengeospatial.org/twiki_public/TemporalDWG/WebHome Temporal Domain Working Group]. These definitions are:
    2222
    23    * [http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/AnsiDate ANSI date] (`OGC:AnsiDate`) : linear count of days (labelled `'ansi'`) since 1^st^ of January 1601, 00h00 UTC (note that decimal coordinates are possible to reference fraction of the day).
    24    * [http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/Temporal?expand=none parametrized temporal CRS] (`OGC:Temporal`) : parametrized CRS for the user-friendly definition of a custom T-CRS: it resolves to a concrete definition of T-CRS as long as the ''epoch'' and the ''UoM'' are explicitly set in the query of the URI (and optionally an axis label and an axis direction: defaults are `'t'` and `'future'`). !UoMs can be defined as either i) [http://unitsofmeasure.org/ucum.html UCUM] `c/s` codes, ii) actionable URIs pointing to valid GML definition of !UoMs or iii) URIs like ''`http://www.opengis.net/def/uom/UCUM/0/<code>`'' (which the OGC SISSVoc resolver redirects to the UCUM web page and from which ''Petascope'' extracts the ''`<code>`''); please note that our ISO timestamp parser relies on UCUM codes, so using unconventional abbreviations or definitions is not recommended here.
     23   * [http://rasdaman.org:8080/def/crs/OGC/0/AnsiDate ANSI date] (`OGC:AnsiDate`) : linear count of days (labelled `'ansi'`) since 1^st^ of January 1601, 00h00 UTC (note that decimal coordinates are possible to reference fraction of the day).
     24   * [http://rasdaman.org:8080/def/crs/OGC/0/Temporal?expand=none parametrized temporal CRS] (`OGC:Temporal`) : parametrized CRS for the user-friendly definition of a custom T-CRS: it resolves to a concrete definition of T-CRS as long as the ''epoch'' and the ''UoM'' are explicitly set in the query of the URI (and optionally an axis label and an axis direction: defaults are `'t'` and `'future'`). !UoMs can be defined as either i) [http://unitsofmeasure.org/ucum.html UCUM] `c/s` codes, ii) actionable URIs pointing to valid GML definition of !UoMs or iii) URIs like ''`http://www.opengis.net/def/uom/UCUM/0/<code>`'' (which the OGC SISSVoc resolver redirects to the UCUM web page and from which ''Petascope'' extracts the ''`<code>`''); please note that our ISO timestamp parser relies on UCUM codes, so using unconventional abbreviations or definitions is not recommended here.
    2525
    2626For a full list of time resources under review by OGC-NA please visit [http://external.opengeospatial.org/twiki_public/TemporalDWG/TemporalCrsUris this page] (active participation is also appreciated via [https://lists.opengeospatial.org/mailman/listinfo/temporal mailing list]). After official acknowledgment of such resources, all of them will be provided by our resolver and additionally by the official [http://www.opengis.net/def/crs/ opengis] servers.
     
    3636After defining it, then you might want to replace your `OGC:Temporal` parametrized URI of, say, Unix time, with your URI:
    3737
    38   * ~~[http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/Temporal?epoch=%222013-02-20T00:00:00Z%22%26uom=%22min%22%26label=%22simulation_time%22 http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/Temporal?epoch="1970-01-01T00:00:00Z"&uom="s"&label="unix_time"]~~
     38  * ~~[http://rasdaman.org:8080/def/crs/OGC/0/Temporal?epoch=%222013-02-20T00:00:00Z%22%26uom=%22min%22%26label=%22simulation_time%22 http://rasdaman.org:8080/def/crs/OGC/0/Temporal?epoch="1970-01-01T00:00:00Z"&uom="s"&label="unix_time"]~~
    3939  * [http://www.schemacentral.com/sc/niem21/e-gml32_TemporalCRS.html http://mydomain.com/def/crs/MYAUTHORITY/<version>/UnixTime]
    4040
    4141'''Parametrizations''' are also useful when one needs to compound together more than one T-CRS of the same kind: this can happen especially e.g. when numerical models are applied daily (real time axis) targeting a set of future days (simulation time axis). Using the same T-CRS makes sense here (let's pick `OGC:AnsiDate` for example), but in order to avoid a clash in the labels of the axes we need to actually use two different URIs in the composition of the CRS, for instance:
    4242
    43    * real-time : [http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/AnsiDate?axis-label=%22real_time%22 http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/AnsiDate?axis-label="real_time"]
    44    * simulation-time : [http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/AnsiDate?axis-label=%22simulation_time%22 http://kahlua.eecs.jacobs-university.de:8080/def/crs/OGC/0/AnsiDate?axis-label="simulation_time"]
     43   * real-time : [http://rasdaman.org:8080/def/crs/OGC/0/AnsiDate?axis-label=%22real_time%22 http://rasdaman.org:8080/def/crs/OGC/0/AnsiDate?axis-label="real_time"]
     44   * simulation-time : [http://rasdaman.org:8080/def/crs/OGC/0/AnsiDate?axis-label=%22simulation_time%22 http://rasdaman.org:8080/def/crs/OGC/0/AnsiDate?axis-label="simulation_time"]
    4545
    4646In case you want to exploits the parametrizations of 'OGC:Temporal' CRS or you want to create a new one, you can adopt the following UCUM-compliant time units: