Article

From tensor and suffix notation to APL

May 1986
ACM SIGAPL APL Quote Quad 16(4):59-64

DOI:10.1145/22008.22017

Authors:

It is well known that multi-dimensional algebraic variables and expressions as well as multivariate equations and functions can be favorably described by means of tensor and/or general suffix notation. In this notation otherwise complicated and obscure formulas can reveal their inherently mostly simple structure making it transparent to the reader. Unfortunately, this structure is hidden behind the compact notation of ordinary matrix algebra and AFL. The paper provides a valuable way for the formal transfer of simple yet characteristic tensor or suffix expressions into equivalent APL statements. By highlighting the essential primitive and basic user-defined APL functions pertinent to this topic, both the advantages and limitations of APL are shown.

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