Description of array

array<OneD = dense<>, int MemLoc=internal>		Programmers Guide
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Category:containers,selectors

Component type:type

Description

This storage type gives an "array of pointers" style implementation of a matrix. Each row or column of the matrix is allocated separately. The type of vector used for the rows or columns is very flexible, and one can choose from any of the OneD storage types, which include dense, compressed, sparse_pair, tree, and linked_list.

 matrix < double,
          rectangle<>,
          array< dense<> >,
          row_major >::type
 [ ] -> [  1  0  0  4  0 ]
 [ ] -> [  0  7  8  0  0 ]
 [ ] -> [ 11  0 13 14  0 ]
 [ ] -> [ 16  0 18  0 20 ]
 [ ] -> [  0 22  0 24  0 ]

 matrix < double, 
          rectangle<>,
          array< sparse_pair<> >,
          row_major >::type
 [ ] -> [ (1,0) (4,3) ]
 [ ] -> [ (7,1) (8,2) ]
 [ ] -> [ (11,0) (13,2) (14,3) ]
 [ ] -> [ (16,0) (18,2) (20,4) ]
 [ ] -> [ (22,1) (24,3) ]

One advantage of this type of storage is that rows can be swapped in constant time. For instance, one could swap the row 3 and 4 of a matrix in the following way.

 Matrix::OneD tmp = A[3];
 A[3] = A[4];
 A[4] = tmp;

The rows are individually reference counted so that the user does not have to worry about deallocating the rows.

Example

Definition

matrix.h

Template Parameters

Parameter	Description	Default
`OneD`	The storage type used for each row/column of the matrix	`dense`
`MemLoc`	Specify whether the memory used is "owned" by the matrix or if it was provided to the matrix from some external source (with a pointer to some data)	`internal`

Model of

TwoDStorage

Members

Member	Where defined	Description
`size_type`
`enum { id=ARRAY, oned_id=OneD::id, ext=MemLoc, issparse = OneD::issparse, index=index_from_zero }`

New members

Notes

See also