! D01GBF Example Program Text ! Mark 24 Release. NAG Copyright 2012. Module d01gbfe_mod ! D01GBF Example Program Module: ! Parameters and User-defined Routines ! .. Use Statements .. Use nag_library, Only: nag_wp ! .. Implicit None Statement .. Implicit None ! .. Parameters .. Integer, Parameter :: lenwrk = 500, maxcls = 20000, & ndim = 4, nout = 6 Contains Function functn(ndim,x) ! .. Function Return Value .. Real (Kind=nag_wp) :: functn ! .. Scalar Arguments .. Integer, Intent (In) :: ndim ! .. Array Arguments .. Real (Kind=nag_wp), Intent (In) :: x(ndim) ! .. Intrinsic Procedures .. Intrinsic :: exp ! .. Executable Statements .. functn = 4.0E0_nag_wp*x(1)*x(3)**2*exp(2.0E0_nag_wp*x(1)*x(3))/ & (1.0E0_nag_wp+x(2)+x(4))**2 Return End Function functn End Module d01gbfe_mod Program d01gbfe ! D01GBF Example Main Program ! .. Use Statements .. Use nag_library, Only: d01gbf, nag_wp Use d01gbfe_mod, Only: functn, lenwrk, maxcls, ndim, nout ! .. Implicit None Statement .. Implicit None ! .. Local Scalars .. Real (Kind=nag_wp) :: acc, eps, finest Integer :: ifail, mincls ! .. Local Arrays .. Real (Kind=nag_wp), Allocatable :: a(:), b(:), wrkstr(:) ! .. Executable Statements .. Write (nout,*) 'D01GBF Example Program Results' Allocate (a(ndim),b(ndim),wrkstr(lenwrk)) a(1:ndim) = 0.0E0_nag_wp b(1:ndim) = 1.0E0_nag_wp eps = 0.01E0_nag_wp mincls = 1000 ifail = -1 Call d01gbf(ndim,a,b,mincls,maxcls,functn,eps,acc,lenwrk,wrkstr,finest, & ifail) Select Case (ifail) Case (0,2) Write (nout,*) Write (nout,99998) 'Requested accuracy = ', eps Write (nout,99997) 'Estimated value = ', finest Write (nout,99998) 'Estimated accuracy = ', acc Write (nout,99999) 'Number of evaluations = ', mincls End Select 99999 Format (1X,A,I5) 99998 Format (1X,A,E13.2) 99997 Format (1X,A,F13.5) End Program d01gbfe