SAC-1 variable precision floating point arithmetic

  • Authors:
  • James R. Pinkert

  • Affiliations:
  • -

  • Venue:
  • ACM '75 Proceedings of the 1975 annual conference
  • Year:
  • 1975

Quantified Score

Hi-index 0.00

Visualization

Abstract

With most FORTRAN implementations, each variable V in a user's program is characterized at compile time as V(B, M, N) to specify that V can store exactly only values of the form ±b1b2... bm x B±n, where the bj are B-digits, m ≤ M, and n ≤ N. One typical triple is (16, 6, 64). A system has been developed in which (108, 103, 108) is readily attainable, and M can be changed during execution. To achieve efficiency and portability, the implementation makes extensive use of the SAC-1 system developed by George Collins. This paper describes the routines comprising the system, and discusses a sample application, Theoretical and empirical computing times are also presented.