NAG Library Manual, Mark 29.3
Interfaces:  FL   CL   CPP   AD 

NAG AD Library Introduction
Example description
    Program f01ej_p0w_fe

!     F01EJ_P0W_F Example Program Text

!     Mark 29.3 Release. NAG Copyright 2023.

!     .. Use Statements ..
      Use iso_c_binding, Only: c_ptr
      Use nagad_library, Only: f01ej_p0w_f
      Use nag_library, Only: nag_wp, x04caf
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Type (c_ptr)                     :: ad_handle
      Real (Kind=nag_wp)               :: imnorm
      Integer                          :: i, ifail, lda, n
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:)
!     .. Executable Statements ..
      Write (nout,*) 'F01EJ_P0W_F Example Program Results'
      Write (nout,*)
      Flush (nout)

!     Skip heading in data file
      Read (nin,*)
      Read (nin,*) n

      lda = n
      Allocate (a(lda,n))

!     Read A from data file
      Read (nin,*)(a(i,1:n),i=1,n)

!     ifail: behaviour on error exit
!             =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft
      ifail = 0

!     Find log( A )
      Call f01ej_p0w_f(ad_handle,n,a,lda,imnorm,ifail)

!     Print solution
      ifail = 0
      Call x04caf('G','N',n,n,a,lda,'log(A)',ifail)

    End Program f01ej_p0w_fe