Program f01dtfe
! F01DTF Example Program Text
! Mark 30.1 Release. NAG Copyright 2024.
! .. Use Statements ..
Use nag_library, Only: f01dtf, nag_wp, x04daf
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: nin = 5, nout = 6
! .. Local Scalars ..
Complex (Kind=nag_wp) :: alpha, beta
Integer :: i, ifail, lda, ldb, ldc, n
Logical :: lta, ltb, lu
Character (1) :: transa, transb, uplo
! .. Local Arrays ..
Complex (Kind=nag_wp), Allocatable :: a(:,:), b(:,:), c(:,:)
! .. Executable Statements ..
Write (nout,*) 'F01DTF Example Program Results'
! Skip heading in data file
Read (nin,*)
Write (nout,*)
Flush (nout)
! Values for uplo, transa, transb
Read (nin,*) uplo, transa, transb
lu = (uplo=='U')
lta = (transa=='N')
ltb = (transb=='N')
! Order of square matrices
Read (nin,*) n
lda = n
ldb = n
ldc = n
! Scaling constant alpha
Read (nin,*) alpha, beta
! Allocate memory for local arrays
Allocate (a(n,n),b(n,n),c(n,n))
! Read input matrix A from data file
If (lu .Eqv. lta) Then
Read (nin,*)(a(i,i:n),i=1,n)
Else
Read (nin,*)(a(i,1:i),i=1,n)
End If
! Read input matrix B from data file
If (lu .Eqv. ltb) Then
Read (nin,*)(b(i,i:n),i=1,n)
Else
Read (nin,*)(b(i,1:i),i=1,n)
End If
! Read input matrix C from data file
Read (nin,*)(c(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
! Compute the triangular matrix product and update C
Call f01dtf(uplo,transa,transb,n,alpha,a,lda,b,ldb,beta,c,ldc,ifail)
! Print the solution
If (ifail==0) Then
ifail = 0
Call x04daf('G','N',n,n,c,n,'Solution matrix C',ifail)
End If
End Program f01dtfe