NAG Library Manual, Mark 30.1
Interfaces:  FL   CL   CPP   AD 

NAG FL Interface Introduction
Example description
    Program f01jdfe

!     F01JDF Example Program Text

!     Mark 30.1 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: f01jdf, nag_wp, x04caf
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: alpha, condsa
      Integer                          :: i, ifail, lda, n
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:)
!     .. Executable Statements ..
      Write (nout,*) 'F01JDF 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 sqrt(A)
      Call f01jdf(n,a,lda,alpha,condsa,ifail)

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

      Write (nout,*)
      Write (nout,99999) 'Estimated relative condition number is: ', condsa
      Write (nout,99999) 'Condition number for the relative residual is: ',    &
        alpha

99999 Format (1X,A,F6.2)

    End Program f01jdfe