! D01AKF Example Program Text ! Mark 24 Release. NAG Copyright 2012. Module d01akfe_mod ! D01AKF Example Program Module: ! Parameters and User-defined Routines ! .. Use Statements .. Use nag_library, Only: nag_wp ! .. Implicit None Statement .. Implicit None ! .. Parameters .. Integer, Parameter :: lw = 800, nout = 6 Integer, Parameter :: liw = lw/4 Contains Function f(x) ! .. Function Return Value .. Real (Kind=nag_wp) :: f ! .. Scalar Arguments .. Real (Kind=nag_wp), Intent (In) :: x ! .. Intrinsic Procedures .. Intrinsic :: cos, sin ! .. Executable Statements .. f = x*(sin(30.0E0_nag_wp*x))*cos(x) Return End Function f End Module d01akfe_mod Program d01akfe ! D01AKF Example Main Program ! .. Use Statements .. Use nag_library, Only: d01akf, nag_wp, x01aaf Use d01akfe_mod, Only: f, liw, lw, nout ! .. Implicit None Statement .. Implicit None ! .. Local Scalars .. Real (Kind=nag_wp) :: a, abserr, b, epsabs, epsrel, & pi, result Integer :: ifail ! .. Local Arrays .. Real (Kind=nag_wp), Allocatable :: w(:) Integer, Allocatable :: iw(:) ! .. Executable Statements .. Write (nout,*) 'D01AKF Example Program Results' Allocate (w(lw),iw(liw)) pi = x01aaf(pi) epsabs = 0.0E0_nag_wp epsrel = 1.0E-03_nag_wp a = 0.0E0_nag_wp b = 2.0E0_nag_wp*pi ifail = -1 Call d01akf(f,a,b,epsabs,epsrel,result,abserr,w,lw,iw,liw,ifail) If (ifail>=0) Then Write (nout,*) Write (nout,99999) 'A ', 'lower limit of integration', a Write (nout,99999) 'B ', 'upper limit of integration', b Write (nout,99998) 'EPSABS', 'absolute accuracy requested', epsabs Write (nout,99998) 'EPSREL', 'relative accuracy requested', epsrel End If If (ifail>=0 .And. ifail<=3) Then Write (nout,*) Write (nout,99997) 'RESULT', 'approximation to the integral', result Write (nout,99998) 'ABSERR', 'estimate of the absolute error', abserr Write (nout,99996) 'IW(1) ', 'number of subintervals used', iw(1) End If 99999 Format (1X,A6,' - ',A32,' = ',F10.4) 99998 Format (1X,A6,' - ',A32,' = ',E9.2) 99997 Format (1X,A6,' - ',A32,' = ',F9.5) 99996 Format (1X,A6,' - ',A32,' = ',I4) End Program d01akfe