PROGRAM f03bafe ! F03BAF Example Program Text ! Mark 23 Release. NAG Copyright 2011. ! .. Use Statements .. USE nag_library, ONLY : dgetrf, f03baf, nag_wp, x04caf ! .. Implicit None Statement .. IMPLICIT NONE ! .. Parameters .. INTEGER, PARAMETER :: nin = 5, nout = 6 ! .. Local Scalars .. REAL (KIND=nag_wp) :: d INTEGER :: i, id, ifail, info, lda, n ! .. Local Arrays .. REAL (KIND=nag_wp), ALLOCATABLE :: a(:,:) INTEGER, ALLOCATABLE :: ipiv(:) ! .. Executable Statements .. WRITE (nout,*) 'F03BAF Example Program Results' ! Skip heading in data file READ (nin,*) READ (nin,*) n lda = n ALLOCATE (a(lda,n),ipiv(n)) READ (nin,*) (a(i,1:n),i=1,n) ! LU Factorize A ! The NAG name equivalent of dgetrf is f07adf CALL dgetrf(n,n,a,lda,ipiv,info) WRITE (nout,*) FLUSH (nout) ifail = 0 CALL x04caf('G','N',n,n,a,lda,'Array A after factorization',ifail) WRITE (nout,*) WRITE (nout,*) 'Pivots' WRITE (nout,99999) ipiv(1:n) WRITE (nout,*) FLUSH (nout) ifail = 0 CALL f03baf(n,a,lda,ipiv,d,id,ifail) WRITE (nout,99998) d, id WRITE (nout,*) WRITE (nout,99997) d*2.0_nag_wp**id 99999 FORMAT (1X,8(1X,I13)) 99998 FORMAT (1X,'D = ',F13.5,' ID = ',I12) 99997 FORMAT (1X,'Value of determinant = ',E13.5) END PROGRAM f03bafe