2-Jul-96, 6:54:35
Routine Save for Matrix Mathematics Library function $%MTXDET^MATH
 ;
 ; Unless otherwise noted, the code below
 ; was approved in document X11/96-26
 ;
 ; If corrections have been applied,
 ; first the original line appears,
 ; with three semicolons at the beginning of the line.
 ;
 ; Then the source of the correction is acknowledged,
 ; then the corrected line appears, followed by a
 ; line containing three semicolons.
 ;
MTXDET(A,N) ;
 ; Compute determinant of matrix A[N,N]
 IF $DATA(A)<10 QUIT ""
 IF $GET(N)<1 QUIT ""
 ;
 ; First the simple cases
 ;
 IF N=1 QUIT $GET(A(1,1))
 IF N=2 QUIT $GET(A(1,1))*$GET(A(2,2))-($GET(A(1,2))*$GET(A(2,1)))
 ;
 NEW DET,I,SIGN
 ;
 ; Det A = sum (k=1:n) element (i,k) * cofactor [i,k]
 ;
 SET DET=0,SIGN=1
 FOR I=1:1:N DO
 . SET DET=$GET(A(1,I))*$%MTXCOF^MATH(.A,1,I,N)*SIGN+DET
 . SET SIGN=-SIGN
 . QUIT
 QUIT DET
 ;===
 ;
 ;
 ;