Matrix   Matrix Overview When to Use Constant Form Object Data Types Examples

Matrix Overview

A Matrix is a one, two, or three dimensional array. An un-typed matrix (also known as a Normal Matrix) is a data structure containing an arbitrary number of heterogeneous data values and with a rank of one, two, or three.

The Matrix is a dynamic data type: it can grow to containing new elements or contract as elements are deleted. An element is accessed by an index from 0 to n-1 where n is the number of elements in the Matrix. When an element is added, it is appended to the end.

Or we might sort the Matrix

Or we might delete a key by specify the index of the item to be deleted (2)

When to Use

The Matrix object is useful for storing data of the "same" types (homogeneous) or "different" types (heterogeneous) . The Matrix object is very fast and has minimum memory overhead due to the indexed access of its values. If you require a random access strategy or a keyed access strategy see the Dictionary or Structure data types. Within the Matrix object type there are the subtypes that store homogeneous values:

Matrix

NumMatrix

Constant Form

The Matrix native data type has a constant form. A Matrix constant is enclosed in brackets and preceded by the sharp symbol (#).

For Example:

#(mat| 0 1 2 3 4 5 6 7 8 9)

The constant form for Matrix allows any Analytic Information Server objects:

#(mat| X: 5 #Jan,1,1996 #{Mike: "father" Sally: "mother"} "Hello")

#(mat| 23 34 "Testing" -.987 #\return)

#(mat| "Hello" 9 34.5)

#(mat| 0 1 2 3 4 5 6 7 8 9 . {a: 10 b: 20})

Object Data Types

The Matrix is a Heap Object or an Object Data Type. The Analytic Information Server Object Types are stored in the Heap and are managed by the Heap manager. The Analytic Information Server Heap manager supports object resizing, garbage collection, and anti-fragmentation algorithms so that the user may concentrate on the analysis and modeling of data rather than on memory management. Without exception, all of the Object types are identified by an object id. The object id identifies a block of memory, managed by the Lambda Information Server memory manager, in which the Object's data is stored.

The Analytic Information Server Heap Object and Native Data types can be saved and loaded to and from persistent (disk file) storage at any time. Containers with immediate data are saved on disk in fixed length records equal to the size of the container. Containers with Heap object references are saved in fixed length records, which are automatically expanded to include the contents of the Heap object, and any objects referenced by the Heap object, etc. This feature is called Object Closure Management and is automatic with every Analytic Information Server container database save.

Analytic Information Server containers may be loaded from any database repository record at any time. If the data in the record is immediate, the database load fills the container with the immediate data. If the data in the record is an object closure, the database load fills the container with a Heap object reference, and all of the objects in the record are loaded back into the Heap with the same referential relationships they had when they were saved in the repository.

The Matrix object can be demonstrated by the following examples.