1 / 23

Feature Collections Subsetting

Feature Collections Subsetting. 1. Overview 2. NCSS 2.1. Dataset description 2.2. Grid requests 2.3. Grid as point requests 3. CdmrFeature. Feature Collections Subsetting 1.Overview. TDS Subsetting services: - Spatial coordinates: - NetCDF Subset Service: NCSS

kory
Download Presentation

Feature Collections Subsetting

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Feature Collections Subsetting 1. Overview 2. NCSS 2.1. Dataset description 2.2. Grid requests 2.3. Grid as point requests 3. CdmrFeature

  2. Feature Collections Subsetting1.Overview • TDS Subsetting services: -Spatial coordinates: - NetCDF Subset Service: NCSS - CDM Remote Feature: CdmrFeature - Array index subsetting: - OpenDAP

  3. Feature Collections Subsetting1.Overview • NetCDF Subset Service: NCSS - Subset on Grid feature collections. - Allows grid subsetting and point extraction.

  4. Feature Collections Subsetting1.Overview • Cdm Remote Feature: CdmrFeature - Subset on point feature collections. - Experimental

  5. Feature Collections Subsetting2.0 NCSS Configuration • - threddsConfig.xml • Enabling the service: <NetcdfSubsetService> <allow>true</allow> <!--maxFileDownloadSize>300 MB</maxFileDownloadSize --> </NetcdfSubsetService> • Enabling netcdf4 as output (optional): <Netcdf4Clibrary> <libraryPath>C:/cdev/lib/</libraryPath> <libraryName>netcdf4</libraryName> </Netcdf4Clibrary> - Catalogs: <service name="subsetServer" serviceType="NetcdfSubset" base="/thredds/ncss/grid/" />

  6. Feature Collections Subsetting2.1. NCSS Dataset description • Document that provides all the information to formulate valid requests • Contains: • coordinate axes • variables • spatial ranges • supported formats • ...

  7. Feature Collections Subsetting2.1. NCSS Dataset description • Two views of the dataset description: • Form view: • Web interface for accessing the service • Simple grid pre-visualization • Xml document

  8. Feature Collections Subsetting2.2. NCSS Grid Subsetting Subsetting on variables • Parameter var (mandatory) • Variables as declared in the dataset description separated by “,” - var=all - var=Pressure_surface,Temperature_tropopause

  9. Feature Collections Subsetting2.2. NCSS Grid Subsetting Spatial subsetting • Lat/Lon bounding box: • params: north, south, west, east (all of them!!!) • var=Pressure_surface,Temperature_tropopause&north=80&south=60&west=200&east=280 • Projection bounding box • params: minx, maxx, miny, maxy (all of them!!!) • var=Pressure_surface,Temperature_tropopause&minx=0&maxx=3000&miny=-1000&maxy=0

  10. Feature Collections Subsetting2.2. NCSS Grid Subsetting Temporal subsetting • By default closest time to present • All range, parameter temporal: • temporal=all • Single time, parameter time (all times in W3C format): • time=2012-10-22T18:00:00Z • Time range (all times and durations in W3C format): • params: time_start, time_end, time_duration (two of them!!!): • time_start=2012-10-22T15:00Z&time_duration=P1DT12H

  11. Feature Collections Subsetting2.2. NCSS Grid Subsetting Vertical subsetting • Default: all vertical levels • vertCoord: only on variables with same vertical levels • vertCoord=400

  12. Feature Collections Subsetting2.2. NCSS Grid Subsetting Vertical subsetting: transformations • If a vertical transformation is defined in the dataset (CF-1.0) all the variables needed to perform the transformation are included in the grid output • Example: http://geoport-dev.whoi.edu/thredds/ncss/grid/coawst_2_2/fmrc/coawst_2_2_best.ncd/dataset.html

  13. Feature Collections Subsetting2.2. NCSS Grid Subsetting Supported Formats • netCDF, netCDF4 • NetCDF4 has to be configured in threddsConfig.xml • Parameter: accept - accept=netcdf - accept=netcdf4

  14. Feature Collections Subsetting2.3. NCSS Grid As Point Grid As Point • Extracts point features from grids • Parameters latitude and longitude to define the requested point - latitude=86&longitude=220

  15. Feature Collections Subsetting2.3. NCSS Grid As Point Vertical levels • All vertical levels are returned by default • Parameter vertCoord can be used on variables with different vertical levels.

  16. Feature Collections Subsetting2.3. NCSS Grid As Point Vertical levels • If a vertical transformation is defined in the dataset the service returns: • The values of the dimensionless vertical coordinate. • The actual values of the vertical levels.

  17. Feature Collections Subsetting2.3. NCSS Grid As Point Supported Formats • csv, xml, netCDF, netCDF4 • NetCDF4 has to be configured in threddsConfig.xml • Parameter: accept - accept=netcdf - accept=netcdf4 - accept=xml - accept=csv

  18. Feature Collections Subsetting3. CdmrFeature • CdmrFeature: subsetting on point feature collections • Still under development. Unstable. • Eventually, NCSS and CdmrFeature will merge into one single API for subsetting grid and point features.

  19. Feature Collections Subsetting3. CdmrFeature • Example requests: Metadata requests • Dataset form • req=form • Dataset description (capabilities): • req=capabilities • Stations: • req=stations

  20. Feature Collections Subsetting3. CdmrFeature • Example requests: Metadata requests • Dataset form • req=form • Dataset description (capabilities): • req=capabilities • Stations: • req=stations

  21. Feature Collections Subsetting3. CdmrFeature Data requests: • req=data • Spatial subsetting: • variables=some • spatial=bb • temporal=range http://thredds.ucar.edu/thredds/cdmrfeature/nws/metar/ncdecoded/Metar_Station_Data_fc.cdmr?req=data&variables=some&var=air_temperature&var=cloud_area_fraction&spatial=bb&north=41&west=-109&east=-102&south=37&temporal=range&time_start=2013-07-09T23:00:00Z&time_end=2013-07-10T00:00:00Z&time=2013-05-10T00:00:00Z&accept=csv

  22. Feature Collections Subsetting3. CdmrFeature • Data requests: • Stations subsetting: • spatial=stns • stn=LEST,LEVX,LECO http://thredds.ucar.edu/thredds/cdmrfeature/nws/metar/ncdecoded/Metar_Station_Data_fc.cdmr?req=data&variables=some&var=air_temperature&spatial=stns&stn=LEST,LEVX,LECO&temporal=range&time_start=2013-07-09T23:00:00Z&time_end=2013-07-10T00:00:00Z&time=2013-05-10T00:00:00Z&accept=csv

  23. Feature Collections Subsetting3. CdmrFeature • Data requests: • Closest station: • spatial=point • Latitude=39.98 • longitude=-105.02 http://thredds.ucar.edu/thredds/cdmrfeature/nws/metar/ncdecoded/Metar_Station_Data_fc.cdmr?req=data&variables=some&var=air_temperature&spatial=point&latitude=39.98&longitude=-105.02&stn=&temporal=range&time_start=2013-07-09T23:00:00Z&time_end=2013-07-10T00:00:00Z&time=2013-05-10T00:00:00Z&accept=csv

More Related