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

NAG FL Interface Introduction
Example description
    Program f11mkfe

!     F11MKF Example Program Text

!     Mark 30.0 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: f11mkf, nag_wp, x04caf
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Real (Kind=nag_wp), Parameter    :: alpha = 1.E0_nag_wp
      Real (Kind=nag_wp), Parameter    :: beta = 0.E0_nag_wp
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Integer                          :: i, ifail, j, ldb, ldc, m, n, nnz
      Character (1)                    :: trans
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: a(:), b(:,:), c(:,:)
      Integer, Allocatable             :: icolzp(:), irowix(:)
!     .. Executable Statements ..
      Write (nout,*) 'F11MKF Example Program Results'
!     Skip heading in data file
      Read (nin,*)

!     Read order of matrix

      Read (nin,*) n, m
      ldb = n
      ldc = n

      Allocate (b(ldb,m),c(ldc,m),icolzp(n+1))

!     Read the matrix A

      Read (nin,*) icolzp(1:n+1)
      nnz = icolzp(n+1) - 1

      Allocate (a(nnz),irowix(nnz))

      Do i = 1, nnz
        Read (nin,*) a(i), irowix(i)
      End Do

!     Read the matrix B

      Do j = 1, m
        Read (nin,*) b(1:n,j)
      End Do

!     Calculate matrix-matrix product

      trans = 'N'

!     ifail: behaviour on error exit
!             =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft
      ifail = 0
      Call f11mkf(trans,n,m,alpha,icolzp,irowix,a,b,ldb,beta,c,ldc,ifail)

!     Output results
      Write (nout,*)
      Flush (nout)

      Call x04caf('G',' ',n,m,c,ldc,'Matrix-matrix product',ifail)

!     Calculate transposed matrix-matrix product
      trans = 'T'

      ifail = 0
      Call f11mkf(trans,n,m,alpha,icolzp,irowix,a,b,ldb,beta,c,ldc,ifail)

!     Output results
      Write (nout,*)
      Flush (nout)

      Call x04caf('G',' ',n,m,c,ldc,'Transposed matrix-matrix product',ifail)

    End Program f11mkfe