A sum-substitutor used as trigonometric simplifier

  • L. Hornfeldt
5. Applications I
Part of the Lecture Notes in Computer Science book series (LNCS, volume 144)


A program is presented that substitutes arbitrary sums. Among other applications, this sum-substitutor has been set up to exploit the relation:
$$sin^2 + \cos ^2 - 1 = 0$$
which it does more intelligently than previous programs, acheaving close to maximal reduction in size (see examples below).

The sumsubstitutor opens the new prospect of "Inverse evaluation" -that is recombina- tion of objects into higher, composed ones. This could greately compress otherwise unmanageably huge output swell from the ever larger machines. The program is a part of STENSOR [3,4,5,6,10] running on the algebraic systems MACSYMA [11] and SHEEP [1,2].


Scalar Part Numeric Coefficient Minimal Form Large Machine Previous Program 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1982

Authors and Affiliations

  • L. Hornfeldt
    • 1
  1. 1.Institute of Theoretical PhysicsUniversity of StockholmStockholmSweden

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