The SDL Component Suite is an industry leading collection of components supporting scientific and engineering computing. Please visit the SDL Web site for more information....


Home MathPack Matrix Classes TIntMatrix, TMatrix and TMat3D Methods ArrayToSparse
See also: CreateSparse, SparseToArray 

ArrayToSparse

Unit:SDL_matrix
Class: TIntMatrix
Declaration: procedure ArrayToSparse (AllocBy: longint);

The method ArrayToSparse converts a normal full array-based representation of the matrix into a sparse matrix. Please note that this conversion is only meaningful for matrices which contain at least 70 % zeroes. Sparse matrices are in general more memory efficient if the matrix contains a high percentage of zeroes, however access to a sparse matrix is much slower.

The parameter AllocBy specifies the number of elements for which memory is allocated in advance. AllocBy should be set approx. 10 % higher than the expected number of non-zero elements in order to ensure maximum performance. The minimum amount of memory required by a sparse matrix is given by 12*AllocBy for TIntMatrix, or 16*AllocBy for TMatrix


Last Update: 2023-Feb-06