Elementary Structured Types 2—the Array

Abstract

The array data type will be introduced by contrasting it with the sequential file. The array data type is like the sequential file type in that in each case their components must all be of the same type. Unlike a sequential file, however, an array has a fixed number of components which are all equally accessible. Consequently the components of an array may be accessed randomly. In particular, to alter the value of an array variable it is not necessary to produce a complete, new value for the array since the appropriate components may be selectively updated.