maspack.solvers

Class FemMatrixGenerator.CRSMatrix

java.lang.Object

maspack.solvers.FemMatrixGenerator.CRSMatrix

Enclosing class:

FemMatrixGenerator

public static class FemMatrixGenerator.CRSMatrix
extends java.lang.Object

Sparse symmetric matrix in the 1-based upper triangular CRS form used by DirectSolver.

Field Summary

Fields

Modifier and Type	Field and Description
int[]	colIdxs 1-based column indices of the upper triangular non-zeros.
int[]	rowOffs 1-based row start offsets, of length size+1.
int	size Number of rows (and columns).
int	type Matrix type, either Matrix.SPD or Matrix.SYMMETRIC.
double[]	vals Values of the upper triangular non-zeros.

Constructor Summary

Constructors

Constructor and Description
CRSMatrix()

Method Summary

Modifier and Type	Method and Description
double[]	copyVals() Returns a copy of the values, so that a solver may destroy them.
long	numFullVals() Returns the number of non-zeros in the full symmetric matrix.
int	numVals() Returns the number of upper triangular non-zeros.
double	residual(double[] x, double[] b) Computes the residual ||M x - b|| for this matrix.
SparseCRSMatrix	toSparseCRSMatrix() Converts this matrix to a SparseCRSMatrix, for use with the Matrix based solver methods.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

size

public int size

Number of rows (and columns).

rowOffs

public int[] rowOffs

1-based row start offsets, of length size+1.

colIdxs

public int[] colIdxs

1-based column indices of the upper triangular non-zeros.

vals

public double[] vals

Values of the upper triangular non-zeros.

type

public int type

Matrix type, either Matrix.SPD or Matrix.SYMMETRIC.

Constructor Detail

CRSMatrix

public CRSMatrix()

Method Detail

numVals

public int numVals()

Returns the number of upper triangular non-zeros.

Returns:

number of stored values

numFullVals

public long numFullVals()

Returns the number of non-zeros in the full symmetric matrix.

Returns:

number of non-zeros in the full matrix

copyVals

public double[] copyVals()

Returns a copy of the values, so that a solver may destroy them.

Returns:

copy of the value array

residual

public double residual(double[] x,
                       double[] b)

Computes the residual ||M x - b|| for this matrix.

Parameters:

x - solution vector

b - right hand side

Returns:

residual norm

toSparseCRSMatrix

public SparseCRSMatrix toSparseCRSMatrix()

Converts this matrix to a SparseCRSMatrix, for use with the Matrix based solver methods. Only the upper triangle is set, as expected by DirectSolver.analyze(Matrix,int,int).

Returns:

matrix in SparseCRSMatrix form