\START82\
\COMMENT=Program file dated 04/10/96, 18:39
\NAME=ESCHELON
:0\->\\@\
:Menu("CHOOSE","ECHELON",E,"REDUCED ECHELON",F)
:Lbl E
:1\->\\@\
:Lbl F
:dim [A]\->\\L1\
:1\->\A
:1\->\B
:Lbl 0
:For(E,A+1,\L1\(1)+1)
:If abs [A](A,B)<1\E\\(-)\6
:Then
:0\->\[A](A,B)
:If E>\L1\(1)
:Then
:If B=\L1\(2)
:Then
:Goto 2
:Else
:B+1\->\B
:Goto 0
:End
:End
:rowSwap([A],A,E)\->\[A]
:End
:End
:*row([A](A,B)\^-1\,[A],A)\->\[A]
:1\->\[A](A,B)
:For(E,A+1,\L1\(1),1)
:*row+(\(-)\[A](E,B),[A],A,E)\->\[A]
:0\->\[A](E,B)
:End
:A+1\->\A
:B+1\->\B
:If A>\L1\(1)
:Goto 2
:If B>\L1\(2)
:Goto 2
:Goto 0
:Lbl 2
:If \@\=1
:Goto D
:\L1\(1)\->\A
:Lbl A
:If A<1
:Goto D
:1\->\B
:Lbl B
:If [A](A,B)=1
:Goto C
:If B=\L1\(2)
:Then
:A-1\->\A
:Goto A
:End
:B+1\->\B
:Goto B
:Lbl C
:For(C,1,A-1)
:*row+(\(-)\[A](C,B),[A],A,C\->\[A]
:End
:A-1\->\A
:Goto A
:Lbl D
:[A]
:Stop
:COPYRIGHT STEPHEN OSTERMILLER 1996
\STOP82\