Fortran portability via models and tools

  • W. S. Brown
  • A. D. Hall
Conference paper

DOI: 10.1007/3-540-08446-0_41

Part of the Lecture Notes in Computer Science book series (LNCS, volume 57)
Cite this paper as:
Brown W.S., Hall A.D. (1977) Fortran portability via models and tools. In: Cowell W. (eds) Portability of Numerical Software. Lecture Notes in Computer Science, vol 57. Springer, Berlin, Heidelberg


This talk is a survey of recent Bell Labs work on FORTRAN-based software portability. Our approach is based on our experience with the ALTRAN language and system for symbolic algebra, and the PORT Library of state-of-the-art procedures for numerical mathematics.

Both ALTRAN and PORT are written in PFORT, a large and mechanically verifiable subset of ANS FORTRAN. To make PFORT programs easier to write and easier to read, we now use an extension called RATFOR and a preprocessor that translates it into PFORT. A more ambitious extension called EFL is under development.

From a theoretical viewpoint the key to all our work on software portability is a model of the computing environments in which our programs will be expected to operate. We assume a hardware-software environment that fully supports the PFORT language and is characterized by parameters (machine constants) in four basic areas: (1) logical unit numbers, (2) word size, (3) integer arithmetic, and (4) floating-point arithmetic. To demonstrate the use of this model, we discuss an algorithm by J. L. Blue for computing the Euclidean norm of a real vector. The algorithm is portable, accurate, and efficient, avoids overflow and underflow, and will be included in the next edition of PORT.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • W. S. Brown
  • A. D. Hall

There are no affiliations available

Personalised recommendations