Introducing the GEON IDV GEON IDV Displays, and Data from UNAVCO and GEON Download & Run the GEON IDV Tutorial ... How to Use the GEON IDV ... More Tips Data Formats: How to Put Your Data in the IDV

GEON IDV Tutorial

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You should have installed the GEON IDV and have it running, as described in the installation page.

Part 2 - CONNECTING TO DATA SOURCES, and BUNDLE FILES

The IDV can read data several ways: from local files on disk, with an HTTP link to a file on another computer, with other Internet 
protocols such as OPeNDAP (DODS) or the Unidata THREDDS system that provide easy-to-read catalogs, and with other web services 
such as WMS (Web Map Servers).

Local Files

You can read in any data file on any file system you have access to on your local system. 
In the Dashboard window, click the tab "Data Choosers," and click on the "Files" tab.
A file browser like you are used to appears in the Dashboard.

First click on the "Data Source Type" selector for the type of data you have, such as "NetCDF Point data files," 
and the popular "I'm feeling lucky" for NetCDF grid files and some other data file types recognized by special file name extensions. 

Click on the filename you want, and click the "Add Source" button. The IDV connects to the data source (file), but no data is read 
into the IDV until you request a display or calculation to be made. Since you may
not have data for the IDV we will not do an example of this. Loading local files will be obvious after the next examples.


Files Online

To connect to files with an HTTP URL address,
in the Dashboard window, click the tab "Data Chooser," and click on the "URLs" tab.

Cut and paste this URL -   

http://geon.unavco.org/unavco/TOPO/YNP_GTNP_topography_30sec.nc 

in the "URL:" entry box (cut Cntl-C and paste Cntl-V).
This is topography data for the Yelowstone National Park area. Then click on the "Add Source" button.

Now set the "Data Source Type" selector
(in the Data Choosers URLs panel) to "netcdf Point Data files."

Add these other data sources the same way -- 

http://geon.unavco.org/unavco/YNP/YNP_GPS_Smith_0003.nc                     (Yellowstone GPS velocity vectors 2000-2003)
http://geon.unavco.org/unavco/YNP/YNP_locations_mags_2000-2003_eq.nc    (Yellowstone seismicity 2000-2003)
http://geon.unavco.org/unavco/YNP/YNP_eq_loc_mag_focmech_73-97.nc       (Yellowstone focal mechanisms, 1973-1997)

This seismic and GPS data was created and provided by Bob Smith, M. Jordan and S. Husen.

After you click on Add Source, the Dashboard will switch to the Fields Selector panel, which shows your selected Data Sources, 
their Fields (parameters or variables) and the Displays (types of displays)  possible for each field.

To display them see 

Making Displays, next.

Catalogs

For files in an online catalog,  in  the Dashboard window, click the tab "Data Choosers," and click on the "Catalogs" tab. 
Catalogs are online access to data with a user-friendly or descriptive data listing by category, rather than obscure URL 
syntax and file names.

Enter the Unidata catalog link http://www.unidata.ucar.edu/georesources/idvcatalog.xml.

Click on the dot left of "Web Map Servers." Click on the dot left of "JPL On Earth."

Click on the item "Blue Marble Next Generation, Global MODIS derived image," and click on "Add Source."
The "Blue Marble" image from JPL will be loaded as a display in your IDV, from the JPL WMS server. 
This is a live conncetection - if you zoom in, the resolution improves; new data is retrieved from JPL.

You might explore all the data from WMS servers listed in the Unidata catalog.



Recent Earthquakes, and Volcanos

You can plot the location of this week's earthquakes using the main menu command
"Displays -> Locations -> Earth -> Earthquakes"   Data is from a USGS RSS feed.

You can plot the location and name of the Earth's volcanos, active and inactive, using the main menu command
"Displays -> Locations -> Earth -> Volcanos." 
The volcano data is from the Smithsonian Global Volcanism Progam, http://www.volcano.si.edu. 
In the display control's "Locations" tab you can see all numerical data, and in the "Selected" tab panel you can see more 
about a volcano, including a photograph. 

Display controls let you change point symbols, colors, and plot density (cluttering). See How to use the IDV. The earthquake label lists magnitude; in the display control's "Locations" tab you can see depths listed, and in the "Selected" tab panel you can see more data about an earthquake including a web link to the USGS Earthquake Center data page for that event.

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BUNDLE FILES

"Bundle files" are files to "capture the state" of the IDV, in particular, to encapsulate data source choices and a particular IDV display of the data. (Bundle files may or may not include the data; the IDV can get the data from online sources if available; it need not be included in the bundle file.)

The IDV can make a bundle file to save any display and its IDV configuration for future use. Simply loading a bundle file into the IDV with the Data Chooser will cause the display to be recreated.

Bundle files can be used to

• Share data depictions with research colleagues. You can attach a text note to a display, too.
• save a particular data source and display to show a data feature of interest
• archive particular observations of value
• prepare classroom materials (IDV displays)
• send homework assignments, including data choices, to students
• receive completed homework assingments from students

To make a bundle file, choose in the main menu File->Save, then browse to a suitable directory location on your computer, and save a file with the file name extension ".xidv." Bunlde files are also called "xidv" files. They are in XML format and may be edited in some cases, if you are careful, but generally they are used only as they are created..

Note that the data used by a bundle file must be available to anyone who may use the file. Data files on your local disk will not be available to most other IDV. Put your data file on an HTTP server to let others use it in the IDV, and make your bunlde file with data source pointing to the URL of the file Put your data file on an HTTP server to let others use it in the IDV, and make your bunlde file with data source pointing to the URL of the file.

Some example bundle files are online and listed below.

For GEON IDV demos, load these bundle files from the UNAVCO server http://geon.unavco.org/unavco/

For example, enter http://geon.unavco.org/unavco/globe_geodynamics.xidv in the Dashboard's Data Chooser, in the URL entry box. When you click "Add Source" the IDV automatically makes the displays specified by the bunlde file, from data sources given in the bundle file.

The bundle files are

http://geon.unavco.org/unavco/globe_geodynamics.xidv
-- globe view of mantle convection-caused temperatures, plus plate motion vectors.

http://geon.unavco.org/unavco/msh.xidv
-- Mt. St. Helens with PBO GPS velocity vectors, local seismicity, topography, and seismic tomography

http://geon.unavco.org/unavco/ynp.xidv
-- Yellowstone National Park area geophysics with 15 data sets

http://geon.unavco.org/unavco/paleoplates_globe_280ma-present.xidv
-- time animation of plate motion from 280 Mybp to now; globe view

http://geon.unavco.org/unavco/msa.xidv
-- Mt. St. Augustine with global eq catalog seismicity showing benioff zone, and topography.

http://geon.unavco.org/unavco/AVO/alaska_plume_points_dispersion.xidv
-- showing time animation of a synthetic particle plume disperion cloud from Mt. St. Augustine eruption, in 3D topography.

http://geon.unavco.org/unavco/XIDV/Arctic_basin_3D_relief_topography.xidv
-- the the 3D relief topography of the Arctic regions.

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