Accession Number:

ADA238680

Title:

PDEF: A Standard File Format for Data Interchange

Descriptive Note:

Final rept. 1 Jun 1989-1 Jun 1990

Corporate Author:

ARMY ENGINEER TOPOGRAPHIC LABS FORT BELVOIR VA

Personal Author(s):

Report Date:

1991-01-01

Pagination or Media Count:

56.0

Abstract:

This report explains a new method of encoding data in a set of files that allows advantages over current formats and methods. A new format is necessary because all current widely-available file formats retain restrictions such as fixed field lengths that are no longer necessary with modern programming languages. In particular, the ability to be parsed by FORTRAN programs was formerly an important requirement. The limitations of FORTRAN lead to file formats that are clumsy and difficult to work with. The proposed format has a simple syntax and flexible semantics. The format is efficient both for computers and people. It is efficient for computers because it makes use of the powerful parsing tools available for the C programming language. It is efficient for people because data descriptions are in a human-readable form and the content of a data file can be understood without a users manual. The bulk of this report is in appendixes which give illustrative examples. Examples are presented for raster, quadtree, and vector data formats since these formats are especially prevalent in spatial data systems, a specialty of the U.S. Army Engineer Topographic Laboratories. PDEF stands for Protean Data Exchange Format.

Subject Categories:

  • Information Science
  • Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE