com.itemanalysis.psychometrics.factoranalysis

Class MatrixUtils

java.lang.Object

com.itemanalysis.psychometrics.factoranalysis.MatrixUtils

public class MatrixUtils
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
MatrixUtils()

Method Summary

Modifier and Type	Method and Description
static org.apache.commons.math3.linear.RealMatrix	getVector(int size, double value) Creates a vector (1 X size matrix) with all elements set to value.
static org.apache.commons.math3.linear.RealMatrix	multiplyElements(org.apache.commons.math3.linear.RealMatrix A, org.apache.commons.math3.linear.RealMatrix B) Elementwise multiplication of elements in two arrays.
static void	multiplyElementsBy(org.apache.commons.math3.linear.RealMatrix A, org.apache.commons.math3.linear.RealMatrix B) Elementwise multiplication of two matrices.
static double	sumMatrix(org.apache.commons.math3.linear.RealMatrix X)

Methods inherited from class java.lang.Object

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

Constructor Detail

MatrixUtils

public MatrixUtils()

Method Detail

multiplyElements

public static org.apache.commons.math3.linear.RealMatrix multiplyElements(org.apache.commons.math3.linear.RealMatrix A,
                                                                          org.apache.commons.math3.linear.RealMatrix B)
                                                                   throws org.apache.commons.math3.exception.DimensionMismatchException

Elementwise multiplication of elements in two arrays. This is equivalent to using A*B in R when both A and B are matrices.

Parameters:

A - a matrix

B - a matrix of the same dimension as A

Returns:

a matrix with elements that are the produce of elements in A and B.

Throws:

org.apache.commons.math3.exception.DimensionMismatchException

multiplyElementsBy

public static void multiplyElementsBy(org.apache.commons.math3.linear.RealMatrix A,
                                      org.apache.commons.math3.linear.RealMatrix B)
                               throws org.apache.commons.math3.exception.DimensionMismatchException

Elementwise multiplication of two matrices.

Parameters:

A - a matrix that is multiplied by the elements of B

B - another matrix

Throws:

org.apache.commons.math3.exception.DimensionMismatchException

getVector

public static org.apache.commons.math3.linear.RealMatrix getVector(int size,
                                                                   double value)

Creates a vector (1 X size matrix) with all elements set to value.

Parameters:

size -

value -

Returns:

sumMatrix

public static double sumMatrix(org.apache.commons.math3.linear.RealMatrix X)