XML and Geodesy: A SOPAC Perspective Paul Jamason, Scripps Orbit and Permanent Array Center IGS Analysis Center Conference, Miami, June 2008

XML and Geodesy: A SOPAC Perspective SOPAC Participants  Director: Yehuda Bock  GPS Analysts:  Peng Fang  Linette Prawirodirdjo  Programmers:  Ruey-Juin Chang  Paul Jamason  Ian MacLeod  Melinda Squibb  System Administrator: George Wadsworth

XML and Geodesy: A SOPAC Perspective XML: An Overview  XML: eXtensible Markup Language  Framework for sharing structured data  Hierarchical tree-like structure  Extensible: users define their own elements and documents by extending base types  Encode data via element names/attributes (self-describing format)  XML schemas  Validation: reduce publication of errors  Translate XML documents (instances) to a variety of formats via stylesheets

XML and Geodesy: A SOPAC Perspective XML Example: siteOffsets.xml ldes ldes T00:00:00 co-seismic Hector Mine EQ north SNIP --

XML and Geodesy: A SOPAC Perspective XSD Example: siteOffsets.xsd <xsd:schema xmlns:xsd=" targetNamespace=" xmlns:geod=" xmlns:gen=" elementFormDefault="qualified" version="1.0.2" xml:lang="en"> <xsd:import namespace=" schemaLocation=" --SNIP-- <xsd:element name="offsetComponentMagnitude" type="geod:offsetComponentMagnitudeType" minOccurs="1" maxOccurs="3"/>

XML and Geodesy: A SOPAC Perspective XML: (Dis)Advantages  Advantages  Set of standards for representing data; speak a common data language  Validation reduces publication of errors  Field formatting  Limit valid entries (e.g., receiver/antenna types)  Existing software:  XML schema creation  XML instance validation  XSLT transformation  Disadvantages  Size  Speed (validation)  Additional work  Difficult to visually interpret  XML Schema creation can be unpleasant  Not for large data files

XML and Geodesy: A SOPAC Perspective XML and Geodesy: Relevant Standards  Open Geospatial Community (OGC): Geographic Markup Language (GML)   Observation Collections  Filter Encoding  Dublin Core Metadata Initiative (DCMI)  Document-related  Classify dates/files/services/creators  Geodesy Standard?  Define a set of xml schemas with core spatial, temporal, nominal parameters, and extend them

XML and Geodesy: A SOPAC Perspective Geodesy XML Candidates  Metadata-oriented  IGS site logs  Processing setup files  Processing software front-ends (e.g., GAMIT)  Bluebooking - NGS geodetic data submission  OrbitML (GMV) - spacecraft flight parameters  RINEX, SINEX headers

XML and Geodesy: A SOPAC Perspective XML: Supporting Software  XML parsers/transformation software available in variety of languages  Java  Perl - Xerces  FORTRAN - xmlf90; xmlfortran  XML schema generation software  oxygenML for Eclipse  Java class generation  XMLBeans

XML and Geodesy: A SOPAC Perspective XML and Geodesy at SOPAC: IGS Site Logs  Overview:

Sample XML IGS Site Log <igsSiteLog xmlns=" xmlns:mi=" xmlns:equip=" xsi:schemaLocation=" xmlns:xsi=" Scripps 5 - Mt. Soledad SIO M006 La Jolla California USA ASHTECH Z-XII3 GPS LP02814 CD T00:00Z T00:00Z ASH701945B_M CR BPA T00:00Z T00:00Z

XML and Geodesy: A SOPAC Perspective XML and Geodesy at SOPAC  Time Series Plotting  GPS analysis input  Historical equipment information  Site motion model terms - apriori coords  Phase center information  GPS coordinate data submission/querying  GML Observation Collections  GML Filter Encoding  GPS time series offsets

XML and Geodesy: A SOPAC Perspective XML and Geodesy: Conclusion  SOPAC: support IGS/INDIGO via XML site log implementation  Widely used in other fields  Encapsulate, control, validate metadata  Appeal to IT staffs