Program f11jsfe ! F11JSF Example Program Text ! Mark 24 Release. NAG Copyright 2012. ! .. Use Statements .. Use nag_library, Only: f11jsf, 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, lwork, maxitn, n, nnz Character (6) :: method Character (1) :: precon ! .. Local Arrays .. Complex (Kind=nag_wp), Allocatable :: a(:), b(:), work(:), x(:) Real (Kind=nag_wp), Allocatable :: rdiag(:) Integer, Allocatable :: icol(:), irow(:), iwork(:) ! .. Executable Statements .. Write (nout,*) 'F11JSF Example Program Results' ! Skip heading in data file Read (nin,*) ! Read algorithmic parameters Read (nin,*) n Read (nin,*) nnz lwork = 7*n + 120 Allocate (a(nnz),b(n),work(lwork),x(n),rdiag(n),icol(nnz),irow(nnz), & iwork(n+1)) Read (nin,*) method, precon Read (nin,*) omega Read (nin,*) tol, maxitn ! 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 F11JSF ! ifail: behaviour on error exit ! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft ifail = 0 Call f11jsf(method,precon,n,nnz,a,irow,icol,omega,b,tol,maxitn,x,rnorm, & itn,rdiag,work,lwork,iwork,ifail) Write (nout,99999) 'Converged in', itn, ' iterations' Write (nout,99998) 'Final residual norm =', rnorm ! Output x Write (nout,99997) x(1:n) 99999 Format (1X,A,I10,A) 99998 Format (1X,A,1P,E16.3) 99997 Format (1X,'(',E16.4,',',E16.4,')') End Program f11jsfe