Matrix

java.lang.Object
- lejos.utility.Matrix

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable
```
public class Matrix
extends java.lang.Object
implements java.lang.Cloneable, java.io.Serializable
```
Matrix implementation derived from the JAMA project

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`private double[][]`	`A` Array for internal storage of elements.
`private int`	`m` Row and column dimensions.
`private int`	`n` Row and column dimensions.
`private static long`	`serialVersionUID`

Constructor Summary

Constructors
Constructor and Description
`Matrix(double[][] A)` Construct a matrix from a 2-D array.
`Matrix(double[][] A, int m, int n)` Construct a matrix quickly without checking arguments.
`Matrix(double[] vals, int m)` Construct a matrix from a one-dimensional packed array
`Matrix(int m, int n)` Construct an m-by-n matrix of zeros.
`Matrix(int m, int n, double s)` Construct an m-by-n constant matrix.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Matrix`	`arrayLeftDivide(Matrix B)` Element-by-element left division, C = A.\B
`Matrix`	`arrayLeftDivideEquals(Matrix B)` Element-by-element left division in place, A = A.\B
`Matrix`	`arrayRightDivide(Matrix B)` Element-by-element right division, C = A./B
`Matrix`	`arrayRightDivideEquals(Matrix B)` Element-by-element right division in place, A = A./B
`Matrix`	`arrayTimes(Matrix B)` Element-by-element multiplication, C = A.*B
`Matrix`	`arrayTimesEquals(Matrix B)`
`private void`	`checkMatrixDimensions(Matrix B)` Check if size(A) == size(B)
`java.lang.Object`	`clone()` Clone the Matrix object.
`static Matrix`	`constructWithCopy(double[][] A)` Construct a matrix from a copy of a 2-D array.
`Matrix`	`copy()` Make a deep copy of a matrix
`double`	`get(int i, int j)` Get a single element.
`double[][]`	`getArray()` Access the internal two-dimensional array.
`double[][]`	`getArrayCopy()` Copy the internal two-dimensional array.
`int`	`getColumnDimension()` Get column dimension.
`double[]`	`getColumnPackedCopy()` Make a one-dimensional column packed copy of the internal array.
`Matrix`	`getMatrix(int[] r, int[] c)` Get a submatrix.
`Matrix`	`getMatrix(int[] r, int j0, int j1)` Get a submatrix.
`Matrix`	`getMatrix(int i0, int i1, int[] c)` Get a submatrix.
`Matrix`	`getMatrix(int i0, int i1, int j0, int j1)` Get a submatrix.
`int`	`getRowDimension()` Get row dimension.
`double[]`	`getRowPackedCopy()` Make a one-dimensional row packed copy of the internal array.
`private double`	`hypot(double a, double b)` sqrt(a^2 + b^2) without under/overflow.
`static Matrix`	`identity(int m, int n)` Generate identity matrix
`Matrix`	`inverse()` Matrix inverse or pseudoinverse
`Matrix`	`minus(Matrix B)` C = A - B
`Matrix`	`minusEquals(Matrix B)` A = A - B
`double`	`norm1()` One norm
`double`	`normF()` Frobenius norm
`double`	`normInf()` Infinity norm
`Matrix`	`plus(Matrix B)` C = A + B
`Matrix`	`plusEquals(Matrix B)` A = A + B
`void`	`print(java.io.PrintStream out)`
`static Matrix`	`random(int m, int n)` Generate matrix with random elements
`void`	`set(int i, int j, double s)` Set a single element.
`void`	`setMatrix(int[] r, int[] c, Matrix X)` Set a submatrix.
`void`	`setMatrix(int[] r, int j0, int j1, Matrix X)` Set a submatrix.
`void`	`setMatrix(int i0, int i1, int[] c, Matrix X)` Set a submatrix.
`void`	`setMatrix(int i0, int i1, int j0, int j1, Matrix X)` Set a submatrix.
`Matrix`	`solve(Matrix B)` Solve A*X = B
`Matrix`	`times(double s)` Multiply a matrix by a scalar, C = s*A
`Matrix`	`times(Matrix B)` Linear algebraic matrix multiplication, A * B
`Matrix`	`timesEquals(double s)` Multiply a matrix by a scalar in place, A = s*A
`double`	`trace()` Matrix trace.
`Matrix`	`transpose()` Matrix transpose.
`Matrix`	`uminus()` Unary minus

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - serialVersionUID
```
private static final long serialVersionUID
```
    See Also:
    
    Constant Field Values
  - A
```
private double[][] A
```
    Array for internal storage of elements.
  - m
```
private int m
```
    Row and column dimensions.
  - n
```
private int n
```
    Row and column dimensions.
- Constructor Detail
  - Matrix
```
public Matrix(int m,
              int n)
```
    Construct an m-by-n matrix of zeros.
    
    Parameters:
    
    m - Number of rows.
    
    n - Number of columns.
  - Matrix
```
public Matrix(int m,
              int n,
              double s)
```
    Construct an m-by-n constant matrix.
    
    Parameters:
    
    m - Number of rows.
    
    n - Number of columns.
    
    s - Fill the matrix with this scalar value.
  - Matrix
```
public Matrix(double[][] A)
       throws java.lang.IllegalArgumentException
```
    Construct a matrix from a 2-D array.
    
    Parameters:
    
    A - Two-dimensional array of doubles.
    
    Throws:
    
    java.lang.IllegalArgumentException - All rows must have the same length
    
    See Also:
    
    constructWithCopy(double[][])
  - Matrix
```
public Matrix(double[][] A,
              int m,
              int n)
```
    Construct a matrix quickly without checking arguments.
    
    Parameters:
    
    A - Two-dimensional array of doubles.
    
    m - Number of rows.
    
    n - Number of colums.
  - Matrix
```
public Matrix(double[] vals,
              int m)
       throws java.lang.IllegalArgumentException
```
    Construct a matrix from a one-dimensional packed array
    
    Parameters:
    
    vals - One-dimensional array of doubles, packed by columns (ala Fortran).
    
    m - Number of rows.
    
    Throws:
    
    java.lang.IllegalArgumentException - Array length must be a multiple of m.
- Method Detail
  - constructWithCopy
```
public static Matrix constructWithCopy(double[][] A)
                                throws java.lang.IllegalArgumentException
```
    Construct a matrix from a copy of a 2-D array.
    
    Parameters:
    
    A - Two-dimensional array of doubles.
    
    Throws:
    
    java.lang.IllegalArgumentException - All rows must have the same length
  - copy
```
public Matrix copy()
```
    Make a deep copy of a matrix
  - clone
```
public java.lang.Object clone()
```
    Clone the Matrix object.
    
    Overrides:
    
    clone in class java.lang.Object
  - getArray
```
public double[][] getArray()
```
    Access the internal two-dimensional array.
    
    Returns:
    
    Pointer to the two-dimensional array of matrix elements.
  - getArrayCopy
```
public double[][] getArrayCopy()
```
    Copy the internal two-dimensional array.
    
    Returns:
    
    Two-dimensional array copy of matrix elements.
  - getColumnPackedCopy
```
public double[] getColumnPackedCopy()
```
    Make a one-dimensional column packed copy of the internal array.
    
    Returns:
    
    Matrix elements packed in a one-dimensional array by columns.
  - getRowPackedCopy
```
public double[] getRowPackedCopy()
```
    Make a one-dimensional row packed copy of the internal array.
    
    Returns:
    
    Matrix elements packed in a one-dimensional array by rows.
  - getRowDimension
```
public int getRowDimension()
```
    Get row dimension.
    
    Returns:
    
    m, the number of rows.
  - getColumnDimension
```
public int getColumnDimension()
```
    Get column dimension.
    
    Returns:
    
    n, the number of columns.
  - get
```
public double get(int i,
                  int j)
```
    Get a single element.
    
    Parameters:
    
    i - Row index.
    
    j - Column index.
    
    Returns:
    
    A(i,j)
  - getMatrix
```
public Matrix getMatrix(int i0,
                        int i1,
                        int j0,
                        int j1)
                 throws java.lang.ArrayIndexOutOfBoundsException
```
    Get a submatrix.
    
    Parameters:
    
    i0 - Initial row index
    
    i1 - Final row index
    
    j0 - Initial column index
    
    j1 - Final column index
    
    Returns:
    
    A(i0:i1,j0:j1)
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - getMatrix
```
public Matrix getMatrix(int[] r,
                        int[] c)
                 throws java.lang.ArrayIndexOutOfBoundsException
```
    Get a submatrix.
    
    Parameters:
    
    r - Array of row indices.
    
    c - Array of column indices.
    
    Returns:
    
    A(r(:),c(:))
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - getMatrix
```
public Matrix getMatrix(int i0,
                        int i1,
                        int[] c)
                 throws java.lang.ArrayIndexOutOfBoundsException
```
    Get a submatrix.
    
    Parameters:
    
    i0 - Initial row index
    
    i1 - Final row index
    
    c - Array of column indices.
    
    Returns:
    
    A(i0:i1,c(:))
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - getMatrix
```
public Matrix getMatrix(int[] r,
                        int j0,
                        int j1)
                 throws java.lang.ArrayIndexOutOfBoundsException
```
    Get a submatrix.
    
    Parameters:
    
    r - Array of row indices.
    
    j0 - Initial column index
    
    j1 - Final column index
    
    Returns:
    
    A(r(:),j0:j1)
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - set
```
public void set(int i,
                int j,
                double s)
```
    Set a single element.
    
    Parameters:
    
    i - Row index.
    
    j - Column index.
    
    s - A(i,j).
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException
  - setMatrix
```
public void setMatrix(int i0,
                      int i1,
                      int j0,
                      int j1,
                      Matrix X)
               throws java.lang.ArrayIndexOutOfBoundsException
```
    Set a submatrix.
    
    Parameters:
    
    i0 - Initial row index
    
    i1 - Final row index
    
    j0 - Initial column index
    
    j1 - Final column index
    
    X - A(i0:i1,j0:j1)
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - setMatrix
```
public void setMatrix(int[] r,
                      int[] c,
                      Matrix X)
               throws java.lang.ArrayIndexOutOfBoundsException
```
    Set a submatrix.
    
    Parameters:
    
    r - Array of row indices.
    
    c - Array of column indices.
    
    X - A(r(:),c(:))
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - setMatrix
```
public void setMatrix(int[] r,
                      int j0,
                      int j1,
                      Matrix X)
               throws java.lang.ArrayIndexOutOfBoundsException
```
    Set a submatrix.
    
    Parameters:
    
    r - Array of row indices.
    
    j0 - Initial column index
    
    j1 - Final column index
    
    X - A(r(:),j0:j1)
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - setMatrix
```
public void setMatrix(int i0,
                      int i1,
                      int[] c,
                      Matrix X)
               throws java.lang.ArrayIndexOutOfBoundsException
```
    Set a submatrix.
    
    Parameters:
    
    i0 - Initial row index
    
    i1 - Final row index
    
    c - Array of column indices.
    
    X - A(i0:i1,c(:))
    
    Throws:
    
    java.lang.ArrayIndexOutOfBoundsException - Submatrix indices
  - transpose
```
public Matrix transpose()
```
    Matrix transpose.
    
    Returns:
    
    A'
  - norm1
```
public double norm1()
```
    One norm
    
    Returns:
    
    maximum column sum.
  - normInf
```
public double normInf()
```
    Infinity norm
    
    Returns:
    
    maximum row sum.
  - normF
```
public double normF()
```
    Frobenius norm
    
    Returns:
    
    sqrt of sum of squares of all elements.
  - uminus
```
public Matrix uminus()
```
    Unary minus
    
    Returns:
    
    -A
  - plus
```
public Matrix plus(Matrix B)
```
    C = A + B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A + B
  - plusEquals
```
public Matrix plusEquals(Matrix B)
```
    A = A + B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A + B
  - minus
```
public Matrix minus(Matrix B)
```
    C = A - B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A - B
  - minusEquals
```
public Matrix minusEquals(Matrix B)
```
    A = A - B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A - B
  - arrayTimes
```
public Matrix arrayTimes(Matrix B)
```
    Element-by-element multiplication, C = A.*B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A.*B
  - arrayTimesEquals
```
public Matrix arrayTimesEquals(Matrix B)
```
  - arrayRightDivide
```
public Matrix arrayRightDivide(Matrix B)
```
    Element-by-element right division, C = A./B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A./B
  - arrayRightDivideEquals
```
public Matrix arrayRightDivideEquals(Matrix B)
```
    Element-by-element right division in place, A = A./B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A./B
  - arrayLeftDivide
```
public Matrix arrayLeftDivide(Matrix B)
```
    Element-by-element left division, C = A.\B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A.\B
  - arrayLeftDivideEquals
```
public Matrix arrayLeftDivideEquals(Matrix B)
```
    Element-by-element left division in place, A = A.\B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    A.\B
  - times
```
public Matrix times(double s)
```
    Multiply a matrix by a scalar, C = s*A
    
    Parameters:
    
    s - scalar
    
    Returns:
    
    s*A
  - timesEquals
```
public Matrix timesEquals(double s)
```
    Multiply a matrix by a scalar in place, A = s*A
    
    Parameters:
    
    s - scalar
    
    Returns:
    
    replace A by s*A
  - times
```
public Matrix times(Matrix B)
             throws java.lang.IllegalArgumentException
```
    Linear algebraic matrix multiplication, A * B
    
    Parameters:
    
    B - another matrix
    
    Returns:
    
    Matrix product, A * B
    
    Throws:
    
    java.lang.IllegalArgumentException - Matrix inner dimensions must agree.
  - trace
```
public double trace()
```
    Matrix trace.
    
    Returns:
    
    sum of the diagonal elements.
  - random
```
public static Matrix random(int m,
                            int n)
```
    Generate matrix with random elements
    
    Parameters:
    
    m - Number of rows.
    
    n - Number of colums.
    
    Returns:
    
    An m-by-n matrix with uniformly distributed random elements.
  - identity
```
public static Matrix identity(int m,
                              int n)
```
    Generate identity matrix
    
    Parameters:
    
    m - Number of rows.
    
    n - Number of colums.
    
    Returns:
    
    An m-by-n matrix with ones on the diagonal and zeros elsewhere.
  - inverse
```
public Matrix inverse()
```
    Matrix inverse or pseudoinverse
    
    Returns:
    
    inverse(A) if A is square, pseudoinverse otherwise.
  - solve
```
public Matrix solve(Matrix B)
```
    Solve A*X = B
    
    Parameters:
    
    B - right hand side
    
    Returns:
    
    solution if A is square, least squares solution otherwise
  - print
```
public void print(java.io.PrintStream out)
```
  - checkMatrixDimensions
```
private void checkMatrixDimensions(Matrix B)
                            throws java.lang.IllegalArgumentException
```
    Check if size(A) == size(B)
    
    Throws:
    
    java.lang.IllegalArgumentException
  - hypot
```
private double hypot(double a,
                     double b)
```
    sqrt(a^2 + b^2) without under/overflow.
    
    Parameters:
    
    a -
    
    b -
    
    Returns:

Class Matrix

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

serialVersionUID

A

m

n

Constructor Detail

Matrix

Matrix

Matrix

Matrix

Matrix

Method Detail

constructWithCopy

copy

clone

getArray

getArrayCopy

getColumnPackedCopy

getRowPackedCopy

getRowDimension

getColumnDimension

get

getMatrix

getMatrix

getMatrix

getMatrix

set

setMatrix

setMatrix

setMatrix

setMatrix

transpose

norm1

normInf

normF

uminus

plus

plusEquals

minus

minusEquals

arrayTimes

arrayTimesEquals

arrayRightDivide

arrayRightDivideEquals

arrayLeftDivide

arrayLeftDivideEquals

times

timesEquals

times

trace

random

identity

inverse

solve

print

checkMatrixDimensions

hypot