Efficient type inference and coercion in computer algebra

  • Albrecht Fortenbacher
Symbolic And Algebraic Computation — Implementation Methods And Techniques
Part of the Lecture Notes in Computer Science book series (LNCS, volume 429)


Computer algebra systems of the new generation, like Scratchpad, are characterized by a very rich type concept, which models the relationship between mathematical domains of computation. To use these systems interactively, however, the user should be freed of type information. A type inference mechanism determines the appropriate function to call. All known models which allow to define a semantics for type inference cannot express the rich “mathematical” type structure, so presently type inference is done heuristically. The following paper defines a semantics for a subproblem therof, namely coercion, which is based on rewrite rules. From this definition, an efficient coercion algorithm for Scratchpad is constructed using graph techniques.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • Albrecht Fortenbacher
    • 1
  1. 1.Scientific Center Heidelberg, IBM Deutschland GmbHGermany

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