Package org.ejml.sparse.csc

Class MatrixFeatures_DSCC

java.lang.Object

org.ejml.sparse.csc.MatrixFeatures_DSCC

public class MatrixFeatures_DSCC
extends Object

Functions for computing the features/properties of matrices.

Method Summary

Modifier and Type	Method	Description
static boolean	hasUncountable(DMatrixSparseCSC A)
static boolean	isEquals(DMatrixSparseCSC a, DMatrixSparseCSC b)
static boolean	isEquals(DMatrixSparseCSC a, DMatrixSparseCSC b, double tol)
static boolean	isEqualsSort(DMatrixSparseCSC a, DMatrixSparseCSC b, double tol)
static boolean	isIdenticalSort(DMatrixSparseCSC a, DMatrixSparseCSC b, double tol)
static boolean	isIdentity(DMatrixSparseCSC A, double tol)
static boolean	isLowerTriangle(DMatrixSparseCSC A, int hessenberg, double tol)	Checks to see if a matrix is lower triangular or Hessenberg.
static boolean	isOrthogonal(DMatrixSparseCSC Q, double tol)	Checks to see if a matrix is orthogonal or isometric.
static boolean	isPositiveDefinite(DMatrixSparseCSC A)	Checks to see if the matrix is positive definite.
static boolean	isSameStructure(DMatrixSparseCSC a, DMatrixSparseCSC b)	Checks to see if the two matrices have the same shape and same pattern of non-zero elements
static boolean	isSymmetric(DMatrixSparseCSC A, double tol)	Checks to see if the matrix is symmetric to within tolerance.
static boolean	isTranspose(DMatrixSparseCSC A, DMatrixSparseCSC B, double tol)
static boolean	isVector(DMatrixSparseCSC a)	Returns true if the input is a vector
static boolean	isZeros(DMatrixSparseCSC A, double tol)

Methods inherited from class java.lang.Object

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

Method Details

isEquals

public static boolean isEquals(DMatrixSparseCSC a,
 DMatrixSparseCSC b)

isEquals

public static boolean isEquals(DMatrixSparseCSC a,
 DMatrixSparseCSC b,
 double tol)

isEqualsSort

public static boolean isEqualsSort(DMatrixSparseCSC a,
 DMatrixSparseCSC b,
 double tol)

isIdenticalSort

public static boolean isIdenticalSort(DMatrixSparseCSC a,
 DMatrixSparseCSC b,
 double tol)

isSameStructure

public static boolean isSameStructure(DMatrixSparseCSC a,
 DMatrixSparseCSC b)

Checks to see if the two matrices have the same shape and same pattern of non-zero elements

Parameters:

a - Matrix

b - Matrix

Returns:

true if the structure is the same

hasUncountable

public static boolean hasUncountable(DMatrixSparseCSC A)

isZeros

public static boolean isZeros(DMatrixSparseCSC A,
 double tol)

isIdentity

public static boolean isIdentity(DMatrixSparseCSC A,
 double tol)

isLowerTriangle

public static boolean isLowerTriangle(DMatrixSparseCSC A,
 int hessenberg,
 double tol)

Checks to see if a matrix is lower triangular or Hessenberg. A Hessenberg matrix of degree N has the following property:

a_ij ≤ 0 for all i < j+N

A triangular matrix is a Hessenberg matrix of degree 0. Only the upper most diagonal elements are explicitly checked to see if they are non-zero

Parameters:

A - Matrix being tested. Not modified.

hessenberg - The degree of being hessenberg.

tol - How not zero diagonal elements must be.

Returns:

If it is an upper triangular/hessenberg matrix or not.

isTranspose

public static boolean isTranspose(DMatrixSparseCSC A,
 DMatrixSparseCSC B,
 double tol)

isVector

public static boolean isVector(DMatrixSparseCSC a)

Returns true if the input is a vector

Parameters:

a - A matrix or vector

Returns:

true if it's a vector. Column or row.

isSymmetric

public static boolean isSymmetric(DMatrixSparseCSC A,
 double tol)

Checks to see if the matrix is symmetric to within tolerance.

Parameters:

A - Matrix being tested. Not modified.

tol - Tolerance that defines how similar two values must be to be considered identical

Returns:

true if symmetric or false if not

isPositiveDefinite

public static boolean isPositiveDefinite(DMatrixSparseCSC A)

Checks to see if the matrix is positive definite.

x^T A x > 0
for all x where x is a non-zero vector and A is a symmetric matrix.

Parameters:

A - square symmetric matrix. Not modified.

Returns:

True if it is positive definite and false if it is not.

isOrthogonal

public static boolean isOrthogonal(DMatrixSparseCSC Q,
 double tol)

Checks to see if a matrix is orthogonal or isometric.

Parameters:

Q - The matrix being tested. Not modified.

tol - Tolerance.

Returns:

True if it passes the test.