Program f08jffe
! F08JFF Example Program Text
! Mark 25 Release. NAG Copyright 2014.
! .. Use Statements ..
Use nag_library, Only: dsterf, nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: nin = 5, nout = 6
! .. Local Scalars ..
Integer :: info, n
! .. Local Arrays ..
Real (Kind=nag_wp), Allocatable :: d(:), e(:)
! .. Executable Statements ..
Write (nout,*) 'F08JFF Example Program Results'
! Skip heading in data file
Read (nin,*)
Read (nin,*) n
Allocate (d(n),e(n-1))
! Read T from data file
Read (nin,*) d(1:n)
Read (nin,*) e(1:n-1)
! Calculate the eigenvalues of T
! The NAG name equivalent of dsterf is f08jff
Call dsterf(n,d,e,info)
Write (nout,*)
If (info>0) Then
Write (nout,*) 'Failure to converge.'
Else
Write (nout,*) 'Eigenvalues'
Write (nout,99999) d(1:n)
End If
99999 Format (3X,(9F8.4))
End Program f08jffe