Program f07nsfe ! F07NSF Example Program Text ! Mark 24 Release. NAG Copyright 2012. ! .. Use Statements .. Use nag_library, Only: nag_wp, x04dbf, zsytrf, zsytrs ! .. Implicit None Statement .. Implicit None ! .. Parameters .. Integer, Parameter :: nin = 5, nout = 6 ! .. Local Scalars .. Integer :: i, ifail, info, lda, ldb, lwork, n, & nrhs Character (1) :: uplo ! .. Local Arrays .. Complex (Kind=nag_wp), Allocatable :: a(:,:), b(:,:), work(:) Integer, Allocatable :: ipiv(:) Character (1) :: clabs(1), rlabs(1) ! .. Executable Statements .. Write (nout,*) 'F07NSF Example Program Results' ! Skip heading in data file Read (nin,*) Read (nin,*) n, nrhs lda = n ldb = n lwork = 64*n Allocate (a(lda,n),b(ldb,nrhs),work(lwork),ipiv(n)) ! Read A and B from data file Read (nin,*) uplo If (uplo=='U') Then Read (nin,*)(a(i,i:n),i=1,n) Else If (uplo=='L') Then Read (nin,*)(a(i,1:i),i=1,n) End If Read (nin,*)(b(i,1:nrhs),i=1,n) ! Factorize A ! The NAG name equivalent of zsytrf is f07nrf Call zsytrf(uplo,n,a,lda,ipiv,work,lwork,info) Write (nout,*) Flush (nout) If (info==0) Then ! Compute solution ! The NAG name equivalent of zsytrs is f07nsf Call zsytrs(uplo,n,nrhs,a,lda,ipiv,b,ldb,info) ! Print solution ! ifail: behaviour on error exit ! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft ifail = 0 Call x04dbf('General',' ',n,nrhs,b,ldb,'Bracketed','F7.4', & 'Solution(s)','Integer',rlabs,'Integer',clabs,80,0,ifail) Else Write (nout,*) 'The factor D is singular' End If End Program f07nsfe