The philosophy of nothing and everything

ABSTRACT

Perhaps inspired by the IEEE floating point arithmetic standard's introduction of a representation for aberrant numbers, such as the reciprocal of zero, the J interpreter overtly deals with infinites and indeterminacies.This step got rid of some domain error messages, but brought in a few new difficulties, and exposed inconsistencies in the behaviour of elementary arithmetic functions presumably as delivered by the C compilers used for the J interpreters.This paper proposes notation that would allow the J interpreter better to deal with failures of arithmetic. The discussion should assist development of arithmetic for other interpreters and compilers.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.2 Language Classifications

          Nouns: J

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.2 Language Classifications

          Nouns: APL
      D.3.4 Processors
          Subjects: Interpreters

  G. Mathematics of Computing
  G.1 NUMERICAL ANALYSIS
      G.1.0 General
          Subjects: Computer arithmetic

General Terms:
Algorithms, Languages, Theory

Keywords:
arithmetic, comparison, floating point, indeterminate, infinity, tolerance, zero