PROGRAM f03bnfe ! F03BNF Example Program Text ! Mark 23 Release. NAG Copyright 2011. ! .. Use Statements .. USE nag_library, ONLY : f03bnf, nag_wp, x04daf, zgetrf ! .. Implicit None Statement .. IMPLICIT NONE ! .. Parameters .. REAL (KIND=nag_wp), PARAMETER :: two = 2.0_nag_wp INTEGER, PARAMETER :: nin = 5, nout = 6 ! .. Local Scalars .. COMPLEX (KIND=nag_wp) :: d INTEGER :: i, ifail, info, lda, n ! .. Local Arrays .. COMPLEX (KIND=nag_wp), ALLOCATABLE :: a(:,:) INTEGER :: id(2) INTEGER, ALLOCATABLE :: ipiv(:) ! .. Intrinsic Functions .. INTRINSIC aimag, real ! .. Executable Statements .. WRITE (nout,*) 'F03BNF 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 zgetrf is f07arf CALL zgetrf(n,n,a,lda,ipiv,info) WRITE (nout,*) FLUSH (nout) ifail = 0 CALL x04daf('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 f03bnf(n,a,lda,ipiv,d,id,ifail) WRITE (nout,99998) d, id WRITE (nout,*) WRITE (nout,99997) two**id(1)*real(d), two**id(2)*aimag(d) 99999 FORMAT (1X,8(1X,I13)) 99998 FORMAT (1X,'D = (',F13.5,',',F13.5,'), ID = (',I0,', ',I0,')') 99997 FORMAT (1X,'Value of determinant = (',E13.5,',',E13.5,')') END PROGRAM f03bnfe