org.xmlcml.euclid

Class IntSquareMatrix

java.lang.Object

org.xmlcml.euclid.IntMatrix

org.xmlcml.euclid.IntSquareMatrix

All Implemented Interfaces:

EuclidConstants

public class IntSquareMatrix
extends IntMatrix

square matrix class IntSquareMatrix represents a square m-x-m matrix. The basic matrix algebra for square matrices is represented here Check out the exciting member functions, which are supported by Exceptions where appropriate. (NB. No attempt has been made to provide numerical robustness and inversion, diagonalisation, etc are as you find them.)

Author:

(C) P. Murray-Rust, 1996

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	IntSquareMatrix.Type type

Field Summary

Fields inherited from class org.xmlcml.euclid.IntMatrix

cols, flmat, rows

Fields inherited from interface org.xmlcml.euclid.EuclidConstants

C_AMP, C_APOS, C_ATSIGN, C_BACKSLASH, C_BACKSPACE, C_CARET, C_COLON, C_COMMA, C_DEL, C_DOLLAR, C_EQUALS, C_FORMFEED, C_HASH, C_LANGLE, C_LBRAK, C_LCURLY, C_LSQUARE, C_MINUS, C_NBSP, C_NEWLINE, C_NL, C_PERCENT, C_PERIOD, C_PIPE, C_PLUS, C_POUND, C_QUERY, C_QUOT, C_RANGLE, C_RBRAK, C_RCURLY, C_RETURN, C_RSQUARE, C_SEMICOLON, C_SHRIEK, C_SLASH, C_SPACE, C_STAR, C_TAB, C_TILDE, C_UNDER, EPS, F_S, NONWHITEPUNC, NONWHITEPUNC0, NONWHITEPUNC0REGEX, ONE_THIRD, PUNC, S_AMP, S_APOS, S_ATSIGN, S_BACKSLASH, S_CARET, S_COLON, S_COMMA, S_DOLLAR, S_EMPTY, S_EQUALS, S_FORMFEED, S_HASH, S_LANGLE, S_LBRAK, S_LCURLY, S_LSQUARE, S_MINUS, S_NEWLINE, S_NL, S_PERCENT, S_PERIOD, S_PIPE, S_PLUS, S_POUND, S_QUERY, S_QUOT, S_RANGLE, S_RBRAK, S_RCURLY, S_RETURN, S_RSQUARE, S_SEMICOLON, S_SHRIEK, S_SLASH, S_SPACE, S_STAR, S_TAB, S_TILDE, S_UNDER, S_WHITEREGEX, TWO_THIRDS, U_S, WHITESPACE

Constructor Summary

Constructors

Constructor and Description
IntSquareMatrix() Constructor.
IntSquareMatrix(int rows) Constructor.
IntSquareMatrix(int[][] matrix) constructor from array.
IntSquareMatrix(int rows, int f) Creates real square matrix with all elements initialized to int value.
IntSquareMatrix(int rows, int[] array) Creates real square matrix from array THE COLUMN IS THE FASTEST MOVING INDEX, that is the matrix is filled as mat(0,0), mat(0,1) ...
IntSquareMatrix(IntMatrix m) shallow copy from IntMatrix the array values are not copied (only the reference)
IntSquareMatrix(IntMatrix m, int lowrow, int lowcol, int rows) Constructor for submatrix of another matrix.
IntSquareMatrix(IntSquareMatrix m) copy constructor.

Method Summary

Modifier and Type	Method and Description
IntSquareMatrix	copyLowerToUpper() copy lower triangle into upper triangle.
IntSquareMatrix	copyUpperToLower() copy upper triangle into lower triangle.
static IntSquareMatrix	diagonal(IntArray f) create diagonal matrix from real matrix.
boolean	isEqualTo(IntSquareMatrix r) are two matrices identical
boolean	isLowerTriangular() is matrix LowerTriangular.
boolean	isSymmetric() is matrix symmetric.
boolean	isUnit() is it a unit matrix.
boolean	isUpperTriangular() is matrix UpperTriangular.
IntArray	lowerTriangle() copy lower triangle into linear array; order: 0,0; 1,0; 1,1; 2,0
IntSquareMatrix	multiply(IntSquareMatrix m) matrix multiplication.
static IntSquareMatrix	outerProduct(IntArray f) Creates square matrix from real matrix.
IntSquareMatrix	plus(IntSquareMatrix m) matrix addition.
void	shallowCopy(IntSquareMatrix m) shallowCopy an existing square matrix.
IntSquareMatrix	subtract(IntSquareMatrix m) matrix subtraction.
int	trace() trace.
void	transpose() transpose.

Methods inherited from class org.xmlcml.euclid.IntMatrix

appendColumnData, appendColumnData, appendRowData, appendRowData, checkNonEmptyMatrix, clearMatrix, columnwiseDivide, createByRows, deleteColumn, deleteColumns, deleteRow, deleteRows, elementAt, elementAt, elementsInRange, extractColumnData, extractColumns, extractRowData, extractRows, extractSubMatrixData, findLargestUniqueElementsInRowColumn, getCols, getFormat, getIntMatrix, getMatrix, getMatrixAsArray, getRows, getTranspose, indexOfLargestElement, indexOfLargestElementInColumn, indexOfLargestElementInRow, indexOfSmallestElement, indexOfSmallestElementInColumn, indexOfSmallestElementInRow, insertColumnData, insertColumnData, insertRowData, insertRowData, insertRows, isEqualTo, isOrthogonal, isSquare, largestElement, largestElementInColumn, largestElementInRow, makeSpaceForNewColumns, multiply, multiply, multiplyBy, multiplyEquals, negative, plus, reorderColumnsBy, reorderRowsBy, replaceColumnData, replaceColumnData, replaceColumnData, replaceRowData, replaceRowData, replaceRowData, replaceSubMatrixData, setAllElements, setElementAt, setFormat, shallowCopy, smallestElement, smallestElementInColumn, smallestElementInRow, subtract, toString, translateByColumn, writeXML

Methods inherited from class java.lang.Object

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

Constructor Detail

IntSquareMatrix

public IntSquareMatrix()

Constructor. This gives a default matrix with cols = rows = 0.

IntSquareMatrix

public IntSquareMatrix(int rows)

Constructor.

Parameters:

rows - number of rows and columns values are set to zero

IntSquareMatrix

public IntSquareMatrix(int rows,
                       int[] array)

Creates real square matrix from array THE COLUMN IS THE FASTEST MOVING INDEX, that is the matrix is filled as mat(0,0), mat(0,1) ... C-LIKE

Parameters:

rows - the final rows and cols of real square matrix

array - of size (rows * rows)

Throws:

EuclidRuntimeException - array size must be multiple of rows

IntSquareMatrix

public IntSquareMatrix(int rows,
                       int f)

Creates real square matrix with all elements initialized to int value.

Parameters:

rows - size of square matrix

f - value of all elements

IntSquareMatrix

public IntSquareMatrix(IntMatrix m,
                       int lowrow,
                       int lowcol,
                       int rows)
                throws EuclidRuntimeException

Constructor for submatrix of another matrix.

Parameters:

m - matrix to slice (need not be square)

lowrow - the start row inclusive (count from 0)

lowcol - the start column inclusive (count from 0)

rows - size of final matrix

Throws:

EuclidRuntimeException

IntSquareMatrix

public IntSquareMatrix(IntSquareMatrix m)

copy constructor.

Parameters:

m - matrix to copy

IntSquareMatrix

public IntSquareMatrix(IntMatrix m)
                throws EuclidRuntimeException

shallow copy from IntMatrix the array values are not copied (only the reference)

Parameters:

m - matrix to copy reference from

Throws:

EuclidRuntimeException - m must be square (that is cols = rows)

IntSquareMatrix

public IntSquareMatrix(int[][] matrix)
                throws EuclidRuntimeException

constructor from array. form from a Java 2-D array (it holds row and column count)

Parameters:

matrix - to copy

Throws:

EuclidRuntimeException - matrix is not square (might even not be rectangular!)

Method Detail

outerProduct

public static IntSquareMatrix outerProduct(IntArray f)

Creates square matrix from real matrix.

Parameters:

f - real array (length rows) multiplied to give outer product

Returns:

square matrix of size rows * rows

diagonal

public static IntSquareMatrix diagonal(IntArray f)

create diagonal matrix from real matrix.

Parameters:

f - real array (length rows)

Returns:

square matrix with elem (i, i) = f(i), else 0

shallowCopy

public void shallowCopy(IntSquareMatrix m)
                 throws EuclidRuntimeException

shallowCopy an existing square matrix.

Parameters:

m - matrix to shallow copy

Throws:

EuclidRuntimeException - m must have the same number of rows and cols as this

isEqualTo

public boolean isEqualTo(IntSquareMatrix r)

are two matrices identical

Parameters:

r - matrix to compare

Returns:

true if equal (see IntMatrix.equals for details)

plus

public IntSquareMatrix plus(IntSquareMatrix m)
                     throws EuclidRuntimeException

matrix addition. adds conformable matrices. Does NOT alter this.

Parameters:

m - matrix to add

Returns:

resultant matrix

Throws:

EuclidRuntimeException - m must have the same number of rows and cols as this

subtract

public IntSquareMatrix subtract(IntSquareMatrix m)
                         throws EuclidRuntimeException

matrix subtraction. subtracts conformable matrices. Does NOT alter this.

Parameters:

m - matrix to subtract from this

Returns:

resultant matrix

Throws:

EuclidRuntimeException - m must have the same number of rows and cols as this

multiply

public IntSquareMatrix multiply(IntSquareMatrix m)
                         throws EuclidRuntimeException

matrix multiplication. multiplies conformable matrices; result is this*m

Parameters:

m - matrix to multiply by

Returns:

new matrix

Throws:

EuclidRuntimeException - m must have the same number of rows as this has cols

trace

public int trace()

trace.

Returns:

the trace

isUnit

public boolean isUnit()

is it a unit matrix.

Returns:

are all diagonals 1 and off-diagonal zero (within Int.isEqual())

isSymmetric

public boolean isSymmetric()

is matrix symmetric.

Returns:

is Int.isEqual(elem(i,j), elem(j,i))

isUpperTriangular

public boolean isUpperTriangular()

is matrix UpperTriangular.

Returns:

true if all bottom triangle excluding diagona Int.isZero()

isLowerTriangular

public boolean isLowerTriangular()

is matrix LowerTriangular. diagonal must also be zero

Returns:

true if all bottom triangle Int.isZero()

copyUpperToLower

public IntSquareMatrix copyUpperToLower()

copy upper triangle into lower triangle. alters this to make it symmetric

Returns:

this as new square matrix

copyLowerToUpper

public IntSquareMatrix copyLowerToUpper()

copy lower triangle into upper triangle. alters this to make it symmetric

Returns:

this as new square matrix

lowerTriangle

public IntArray lowerTriangle()

copy lower triangle into linear array; order: 0,0; 1,0; 1,1; 2,0

Returns:

linear array of size rows * (rows+1) / 2

transpose

public void transpose()

transpose. MODIFIES this