Program f11dsfe ! F11DSF Example Program Text ! Mark 24 Release. NAG Copyright 2012. ! .. Use Statements .. Use nag_library, Only: f11dsf, nag_wp ! .. Implicit None Statement .. Implicit None ! .. Parameters .. Integer, Parameter :: nin = 5, nout = 6 ! .. Local Scalars .. Real (Kind=nag_wp) :: omega, rnorm, tol Integer :: i, ifail, itn, l, lwork, m, maxitn, & n, nnz Character (8) :: method Character (1) :: precon ! .. Local Arrays .. Complex (Kind=nag_wp), Allocatable :: a(:), b(:), work(:), x(:) Integer, Allocatable :: icol(:), irow(:), iwork(:) ! .. Intrinsic Procedures .. Intrinsic :: max ! .. Executable Statements .. Write (nout,*) 'F11DSF Example Program Results' Write (nout,*) ! Skip heading in data file Read (nin,*) ! Read algorithmic parameters Read (nin,*) n Read (nin,*) nnz Read (nin,*) method, precon Read (nin,*) omega Read (nin,*) m, tol, maxitn l = n If (precon=='N' .Or. precon=='n') l = 0 lwork = max(4*n+m*(m+n+5)+l+121,8*n+l+120,2*n*(m+3)+m*(m+2)+l+120, & 11*n+l+120) Allocate (a(nnz),b(n),work(lwork),x(n),icol(nnz),irow(nnz),iwork(2*n+1)) ! Read the matrix A Do i = 1, nnz Read (nin,*) a(i), irow(i), icol(i) End Do ! Read rhs vector b and initial approximate solution x Read (nin,*) b(1:n) Read (nin,*) x(1:n) ! Solve Ax = b using F11DSF ! ifail: behaviour on error exit ! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft ifail = 0 Call f11dsf(method,precon,n,nnz,a,irow,icol,omega,b,m,tol,maxitn,x, & rnorm,itn,work,lwork,iwork,ifail) Write (nout,99999) itn Write (nout,99998) rnorm Write (nout,*) ! Output x Write (nout,*) ' X' Write (nout,99997) x(1:n) 99999 Format (1X,'Converged in',I10,' iterations') 99998 Format (1X,'Final residual norm =',1P,E16.3) 99997 Format (1X,'(',1P,E16.4,',',1P,E16.4,')') End Program f11dsfe