NAG Library Manual, Mark 30
Interfaces:  FL   CL   CPP   AD 

NAG FL Interface Introduction
Example description
    Program c09eafe

!     C09EAF Example Program Text
!     Mark 30.0 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: c09abf, c09eaf, c09ebf, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Integer                          :: i, ifail, lda, ldb, ldca, ldcd,      &
                                          ldch, ldcv, m, n, nf, nwcm, nwcn,    &
                                          nwct, nwl
      Character (12)                   :: mode, wavnam, wtrans
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:,:), b(:,:), ca(:,:), cd(:,:),    &
                                          ch(:,:), cv(:,:)
      Integer                          :: icomm(180)
!     .. Executable Statements ..
      Write (nout,*) 'C09EAF Example Program Results'

!     Skip heading in data file
      Read (nin,*)
!     Read problem parameters.
      Read (nin,*) m, n
      Read (nin,*) wavnam, mode
      Write (nout,99999) wavnam, mode

      lda = m
      ldb = m
      Allocate (a(lda,n),b(ldb,n))

!     Read data array
      Do i = 1, m
        Read (nin,*) a(i,1:n)
      End Do

      Write (nout,99998) 'Input Data                    A'
      Do i = 1, m
        Write (nout,99997) a(i,1:n)
      End Do

!     Query wavelet filter dimensions
      wtrans = 'Single Level'

!     ifail: behaviour on error exit
!     =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft
      ifail = 0
      Call c09abf(wavnam,wtrans,mode,m,n,nwl,nf,nwct,nwcn,icomm,ifail)
      nwcm = nwct/(4*nwcn)

      Allocate (ca(nwcm,nwcn),cd(nwcm,nwcn),cv(nwcm,nwcn),ch(nwcm,nwcn))
      ldca = nwcm
      ldch = nwcm
      ldcv = nwcm
      ldcd = nwcm

      ifail = 0
      Call c09eaf(m,n,a,lda,ca,ldca,ch,ldch,cv,ldcv,cd,ldcd,icomm,ifail)

      Write (nout,99998) 'Approximation coefficients   CA'
      Do i = 1, nwcm
        Write (nout,99997) ca(i,1:nwcn)
      End Do
      Write (nout,99998) 'Diagonal coefficients        CD'
      Do i = 1, nwcm
        Write (nout,99997) cd(i,1:nwcn)
      End Do
      Write (nout,99998) 'Horizontal coefficients      CH'
      Do i = 1, nwcm
        Write (nout,99997) ch(i,1:nwcn)
      End Do
      Write (nout,99998) 'Vertical coefficients        CV'
      Do i = 1, nwcm
        Write (nout,99997) cv(i,1:nwcn)
      End Do

      ifail = 0
      Call c09ebf(m,n,ca,ldca,ch,ldch,cv,ldcv,cd,ldcd,b,ldb,icomm,ifail)

      Write (nout,99998) 'Reconstruction                B'
      Do i = 1, m
        Write (nout,99997) b(i,1:n)
      End Do

99999 Format (/,1X,'DWT ::',/,1X,'       Wavelet : ',A,/,1X,                   &
        '       End mode: ',A)
99998 Format (/,1X,A,' : ')
99997 Format (1X,8(F8.4,1X),:)
    End Program c09eafe