"{ Encoding: utf8 }"

"

 COPYRIGHT (c) 2018 by eXept Software AG

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

"{ Package: 'stx:libbasic2' }"

"{ NameSpace: Smalltalk }"

Matrix variableSubclass:#TwoDimensionalMatrix

	instanceVariableNames:''

	classVariableNames:''

	poolDictionaries:''

	category:'Collections-MultiDimensional'

!

!TwoDimensionalMatrix class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 2018 by eXept Software AG

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

! !

!TwoDimensionalMatrix methodsFor:'accessing'!

subMatrix: aPoint

    |nRows "{Class: SmallInteger }"

     nCols "{Class: SmallInteger }"

     retval retRow retCol |

    nRows := self rows.

    nCols := self columns.

    retval := Matrix newForRows:(nRows-1) cols:(nCols-1).

    retRow := retCol := 1.

    1 to:nRows do:[:r |

        r ~= aPoint x ifTrue: [

            1 to:nCols do:[:c |

                c ~= aPoint y ifTrue: [

                    retval _at: retRow at: retCol put: (self _at: r at: c).

                    retCol := retCol + 1 

                ] 

            ].

            retRow := retRow + 1 

        ].

        retCol := 1 

    ].

    ^ retval

    "

     (Matrix3_3 withAll:#(11 12 13 

                          21 22 23 

                          31 32 33))

        subMatrix:(1 @ 1)  

    "

! !

!TwoDimensionalMatrix methodsFor:'matrix operations'!

minor: aPoint

    ^ (self subMatrix: aPoint) determinantByCofactors

! !

!TwoDimensionalMatrix methodsFor:'queries'!

cofactor:aPoint

    (aPoint x + aPoint y) odd

            ifTrue: [ ^ -1 * (self minor: aPoint) ]

            ifFalse: [ ^ self minor: aPoint ]

! !

!TwoDimensionalMatrix class methodsFor:'documentation'!

version_CVS

    ^ '$Header$'

! !