Due to the current gap in continued funding from the U.S. National Science Foundation (NSF), the NSF Unidata Program Center has temporarily paused most operations. See NSF Unidata Pause in Most Operations for details.
They are specific to eacg kind of file, so you would have to use the whole CDM software stack. Get this source, and look at the ucar.nc2.dataset.grid.GridCoordSys.getLatLonBoundingBox(), and findTimeCoordElement(): ftp://ftp.unidata.ucar.edu/pub/netcdf-java/v2.2.14/ncSrc-2.2.14.zip Ernest To wrote:
Hi John, I was wondering if you could send us some of the java routines you mentioned that could convert geographical and time coordinates to the array indices used by UNIDATA? We would like to take a look at them and see how they may be used in our webservice. Thank you for your attention. Ernest To PhD Student Center for Research in Water Resources University of Texas at Austin3. Our webservice requires the creation of a URL query based on user inputs (such as coordinates of bounding rectangle, time period of interest and parameter of interest) which will then be used to request data from the website. Could you provide information on how to convert geographicalcoordinates(in decimal degrees) and time values (MM/DD/YYYY hh:mm) into the array indices shown in the websiteabove? e.g. time[0:1:0] y[0:1:0] x[0:1:0]this is not trivial, as it depends on the specific file. there are routines in the netcdf-java 2.2 library that can do it. Are you using java?--- John Caron <caron@xxxxxxxxxxxxxxxx> wrote:Hi Ernest: Ernest To wrote:John, My name is Ernest To and I am a student of Dr. Maidment's. Tim Whiteaker and I are trying towrite awebservice that would download total precipitation data for the continental US at resolution of 20kmfromunidata website for a given time and place. Wehaveso far been experimenting with the following link:http://motherlode.ucar.edu:8080/thredds/dodsC/model/NCEP/NAM/CONUS_20km/surface/NAM_CONUS_20km_surface_20060324_1800.grib1.htmlCan we ask you the following questions? 1. What is a .grib1 or a .grib2 file? Is it in netcdf format?no, grib1 and grib2 are WMO formats for gridded data2. We noticed that in the link above (OPENDAP )thereare options for getting a binary file or an ASCII file. Are those files in netcdf and cdl formats respectively?no, they are in opendap specific formats. normally you would use the opendap client library (C++ or Java) to access data through opendap, rather than downloading files.3. Our webservice requires the creation of a URL query based on user inputs (such as coordinates of bounding rectangle, time period of interest and parameter of interest) which will then be used to request data from the website. Could you provide information on how to convert geographicalcoordinates(in decimal degrees) and time values (MM/DD/YYYY hh:mm) into the array indices shown in the websiteabove? e.g. time[0:1:0] y[0:1:0] x[0:1:0]this is not trivial, as it depends on the specific file. there are routines in the netcdf-java 2.2 library that can do it. Are you using java? what file formats can you handle? what does your web service do?Thank you for your kind attention. Please letmeknow if anything is unclear. I can be reachedeitherby e-mail: ernesto_24_7_365@xxxxxxxxx or by phone: 512-508-4834. Thanks. Ernest To PhD student Center for Research in Water Resources University of Texas at Austin 512-508-4834 --- John Caron <caron@xxxxxxxxxxxxxxxx> wrote:Hi David, Ernest: Have a look at the motherlode catalog: http://motherlode.ucar.edu:8080/thredds/ we were guessing you will want the NAM 21-km dataset? If you want to use WCS protocol, you can get back geotiff or netcdf-CF. Otherwise you could use Opendap. There's a few other wrinkles concerning time dimension, we can go over. David Maidment wrote:Ernest: Please see the message below from MohanRamamurthyat Unidata. Can youplease work with John Caron to see how we can ingest a field using webservices. I'd like to stickto something 2D on the land surface like precipitation, evaporation or soilmoisture. I believethose are all in the eta model output. Likely what we want to do is to give alat-long box, a timepoint and a variable, and ask for a field over the region of the lat-long boxfor that variable andtime point, and it might occur that the field actually covers several forecastintervals, eg. 3 hourforecast times for a day. I'm not sure in that case if we should treat eachtimeslice as one field inthe web services ingest, but lets look into what is involved and then figureout what is best.John -- I'd like to see what can be done with aWCS service if possible.Thanks for your help. David -----Original Message-----From: Mohan Ramamurthy [mailto:mohan@xxxxxxxx] Sent: Friday, March 10, 2006 5:40 PMTo: David Maidment Cc: John Caron; Mohan Ramamurthy Subject: Web service to Operational Eta modeloutputDavid, I just spoke to John Caron(caron@xxxxxxxxxxxxxxxx), our lead developeron THREDDS, re. our conversation this afternoontocreate a web serviceto access fields from the operational modeloutputin the IDD stream.John will be happy to work the person on your tomake it happen. Itlooks like many of the pieces are already inplaceto enable a webservice for accessing, subsetting, and movingindividual fields, becausethe data is served via OPeNDAP. For example,hereis the OPeNDAP URLfor today's Eta output:http://motherlode.ucar.edu:8080/thredds/dodsC/model/NCEP/NAM/Alaska_22km/NAM_Alaska_22km_20060310_1200.grib1=== message truncated == __________________________________________________ Do You Yahoo!?Tired of spam? Yahoo! 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