Transformation of Coordinates of Cartographic Digital Data.
Abstract
Map and chart features are now digitized during the semi-automated processes of compilation and chartography so that they may be transformed by computer processing for use in a different format. The resulting magnetic tapes of digital data then are stored in a library or data bank against their possible future use. Topographic maps, charts, and associated graphics are 2-dimensional projections of the 3-dimensional features of the earth's surface. Digitizing-table coordinates and projection, Earth-meter coordinates are plane rectangular systems; geographic, geocentric, and local-secant coordinates are 3-dimensional systems. It is relatively easy to transform coordinates between plane rectangular systems, but it requires rigorous mathematical formulation to transform coordinates between 3-dimensional systems and this process is expensive in computer time.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1974
- Accession Number
- ADA006491
Entities
People
- John F. Codd
Organizations
- Geospatial Research Laboratory