Nested array

From APL Wiki
Revision as of 15:42, 4 November 2019 by Miraheze>Adám Brudzewsky
Jump to navigation Jump to search

In nested array theory, a nested array is an array of depth greater than one, that is, an array that contains at least one element which is not a simple scalar. It is roughly equivalent to a boxed array in flat array theory; more precisely, non-mixed nested arrays correspond exactly to boxed arrays. Depending on language, an empty array may never be considered nested, or it may be considered nested if its prototype is nested.

Scalar functions descend into nested arrays one element at a time. Arrays can be nested at an arbitrary depth so this descent constitutes a traversal. Nested arrays form a tree structure with some additional information (the shape) at each node.

A nested array is a kind of pointer array and is almost always stored using pointers. Template:APL programming language