WPS 4 ODV onthefly serverside plotting of data
- Slides: 17
WPS 4 ODV: on-the-fly server-side plotting of data (in Google Earth) EMODNet chemistry contribution, Barcelona, Mar 2014 Gerben J. de Boer, Gerrit Hendriksen, Giorgio Santinelli 16 juni 2021
Open. Earth. Tools Google Earth static products 16 juni 2021
Matlab oceandataview and googleplot 16 juni 2021
Open. Earth Matlab Google. Plot
Portal links Linkable static collection of png files per granule (made by ODV? ) Linkable static collection of kml files per granule (python or Matlab Linkable DYNAMIC collection of kml files per granule (python) py. WPS *. png ODV batch mode Ø Cache of net. CDF files incl. resolved P 011, P 061 and EDMO codes as NOAA/My. Ocea n THREDDS OPe. NDAP) P 0 x *. nc collection EDMx *. kml Open. Earth Matlab Google. Plot 13, 000 lines *. odv collection > KMLpcolor() wrapper for Simplekml. py > Matplotlib back-end for Simplekml. py SQL/WFS/ SOS/ OPENDAP Ø Cache in RDBMS (Postgre. SQL, Post. GIS or Oracle if someone pays the license) Ø Robo-harvested cache of ODV files Ø ODV files at EDMO sources
py. WPS MSc thesis finished this summer under National GIS MSc program http: //localhost/ tor testing
Processing 1 ODV fle http: //localhost/cgi-bin/pywps. cgi? &service=wps &version=1. 0. 0 &request=Execute &Identifier=odv. Process &Data. Inputs=[ url=d: /. . /userkc 30 e 50 -data_centre 632 -090210_result/… world_N 50 W 10 N 40 E 0_20060101_20070101. txt; parameter=Wind_direction%28 dd%29_[deg] ] 16 juni 2021
WPS output xml with link to kmz kml is inefficient xml so needs zipping for faster delivery kmz is zip file renamed kmz with the kml inside it. a kmz can include more, like the scattered dot png 16 juni 2021
kmz can be opened in Google Earth Value is mapped in a grey scale colormap 16 juni 2021
Data value lights up as text upon mouse hoover-over 16 juni 2021
Data and meta-data is stored as html table inside kmz 16 juni 2021
Time of each data encoded as kml time: time slider to select period 16 juni 2021
WPS output xml with json inside it Java Script Object Notation json is an efficient ascii stream many libraries can easily parse json, especially java script as used in websites webviewer can render table or plot 16 juni 2021
Also for directory with ODV files but a bit slow, ODV has some performance issues for large folders http: //localhost/cgi-bin/pywps. cgi? &service=wps &version=1. 0. 0 &request=Execute &Identifier=odv. Process &Data. Inputs=[ url=d: /. . /userkc 30 e 50 -data_centre 632 -090210_result; parameter=Wind_direction%28 dd%29_[deg] ] 16 juni 2021
SDN integration issues • Speed-up getting the data: needed for on-the-fly • ODV cache • Matlab toolbox • Python py. ODV: quick ‘n dirty parser (scaffolded: no P 01) • API: http: //odv. awi. de • API: ODV collections • Postgre. SQL/Oracle cache (python has mature SQL library) • net. CDF collection cache (python has mature netcdf library) • How to request plot for one variable: • How do you know what’s in a file? Meta-data is too aggregated. • 2 -step query like SOS? • Where to host test WPS server? • Test dataset cache 4 Deltares server? 16 juni 2021
Py. WPS ODV code in open access repos 16 juni 2021
WPS inputs: ideas? WPS input • Colormap choice • Colorlimits • Outputformat: kmz, json, png, … • Flag for pop-up table (slow for large datasets) • Plot options: > Trajectory: connect dots with lines > Timeseries: dynamic plot > Profiles: plot as column with z exaggeration 16 juni 2021
