A graphical calculus

  • Sharon Curtis
  • Gavin Lowe
Contributed Lectures
Part of the Lecture Notes in Computer Science book series (LNCS, volume 947)


We present a graphical calculus, which allows mathematical formulae to be represented and reasoned about using a visual representation. We define how a formula may be represented by a graph, and present a number of laws for transforming graphs, and describe the effects these transformations have on the corresponding formulae. We then use these transformation laws to perform proofs. We illustrate the graphical calculus by applying it to the relational and sequential calculi. The graphical calculus makes formulae easier to understand, and so often makes the next step in a proof more obvious. Furthermore, it is more expressive, and so allows a number of proofs that cannot otherwise be undertaken in a point-free way.


Composition Operator Sequential Relation Graph Transformation Sequential Calculus Local Linearity 
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 1995

Authors and Affiliations

  • Sharon Curtis
    • 1
  • Gavin Lowe
    • 1
  1. 1.Computing LaboratoryOxford UniversityOxfordUK

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