Program f11mefe
! F11MEF Example Program Text
! Mark 30.1 Release. NAG Copyright 2024.
! .. Use Statements ..
Use nag_library, Only: f11mdf, f11mef, nag_wp, x04cbf
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Real (Kind=nag_wp), Parameter :: one = 1.E0_nag_wp
Integer, Parameter :: nin = 5, nout = 6
! .. Local Scalars ..
Real (Kind=nag_wp) :: flop, thresh
Integer :: i, ifail, n, nnz, nnzl, nnzu, nzlmx, &
nzlumx, nzumx
Character (1) :: spec
! .. Local Arrays ..
Real (Kind=nag_wp), Allocatable :: a(:), lval(:), uval(:)
Integer, Allocatable :: icolzp(:), il(:), iprm(:), &
irowix(:), iu(:)
Character (1) :: clabs(1), rlabs(1)
! .. Executable Statements ..
Write (nout,*) 'F11MEF Example Program Results'
Flush (nout)
! Skip heading in data file
Read (nin,*)
! Read order of matrix
Read (nin,*) n
Allocate (icolzp(n+1),iprm(7*n))
! Read the matrix A
Read (nin,*) icolzp(1:n+1)
nnz = icolzp(n+1) - 1
Allocate (a(nnz),lval(8*nnz),uval(8*nnz),il(7*n+8*nnz+4),irowix(nnz), &
iu(2*n+8*nnz+1))
Do i = 1, nnz
Read (nin,*) a(i), irowix(i)
End Do
! Calculate COLAMD permutation
spec = 'M'
! ifail: behaviour on error exit
! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft
ifail = 0
Call f11mdf(spec,n,icolzp,irowix,iprm,ifail)
! Factorise
thresh = one
ifail = 0
nzlmx = 8*nnz
nzlumx = 8*nnz
nzumx = 8*nnz
Call f11mef(n,irowix,a,iprm,thresh,nzlmx,nzlumx,nzumx,il,lval,iu,uval, &
nnzl,nnzu,flop,ifail)
! Output results
Write (nout,99999)
Write (nout,99998) nnzl + nnzu - n
Flush (nout)
Call x04cbf('G','X',1,10,lval,1,'F7.2','Factor elements in LVAL','N', &
rlabs,'N',clabs,80,0,ifail)
Call x04cbf('G','X',1,4,uval,1,'F7.2','Factor elements in UVAL','N', &
rlabs,'N',clabs,80,0,ifail)
99999 Format (1X,/,1X,'Number of nonzeros in factors (excluding unit', &
' diagonal)')
99998 Format (1X,I8)
End Program f11mefe