Parts of arrays-an introduction

Abstract

Traditionally, APL arrays have three parts : shape, type and elements . This notion is extended to include user defined and additional primitive parts. Functions are defined to manipulate parts. Keyed indexing is introduced to define parts, and also as an enhancement in its own right. In this paper, the concept of parts of arrays is introduced at a general level. The definition of parts is illustrated and some examples of their use is given.