Creates a compressed diagonal storage matrix corresponding to a banded square matrix.

Syntax

M = BandMatrix(size, kl, ku)

Arguments

Name

Description

size

The size of each dimension of the original square matrix.

kl

Number of sub-diagonals in the lower band of the original matrix.  This should include zero entry off-diagonals that sit in-between non-zero off-diagonals.

ku

Number of super diagonals in the upper band of the original matrix.  This should include zero entry off-diagonals that sit in-between non-zero off-diagonals.

Output

Name

Description

M

The corresponding compressed diagonal storage matrix initialized with zeros.  The number of rows of M is 2*kl+ku+1 and the number of columns equal size.

Example

Construct the compressed diagonal storage matrix for A, where A is a 3x3 matrix with one sub- and super-diagonal.

Syntax

kl=1; ku=1; // off diagonals

M = BandMatrix(3,kl,ku); // The compressed diagonal storage matrix

Result

M = [Matrix] 4 x 3

0   0   0  

0   0   0

0   0   0

0   0   0

See Also:

BandMatrixIndices

SymBandMatrix