! E04ABA Example Program Text
! Mark 25 Release. NAG Copyright 2014.
Module e04abae_mod
! E04ABA Example Program Module:
! Parameters and User-defined Routines
! .. Use Statements ..
Use nag_library, Only: nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Accessibility Statements ..
Private
Public :: funct
! .. Parameters ..
Integer, Parameter, Public :: nout = 6
Contains
Subroutine funct(xc,fc,iuser,ruser)
! Routine to evaluate F(x) at any point in (A, B)
! .. Scalar Arguments ..
Real (Kind=nag_wp), Intent (Out) :: fc
Real (Kind=nag_wp), Intent (In) :: xc
! .. Array Arguments ..
Real (Kind=nag_wp), Intent (Inout) :: ruser(*)
Integer, Intent (Inout) :: iuser(*)
! .. Intrinsic Procedures ..
Intrinsic :: sin
! .. Executable Statements ..
fc = sin(xc)/xc
Return
End Subroutine funct
End Module e04abae_mod
Program e04abae
! E04ABA Example Main Program
! .. Use Statements ..
Use nag_library, Only: e04aba, nag_wp
Use e04abae_mod, Only: funct, nout
! .. Implicit None Statement ..
Implicit None
! .. Local Scalars ..
Real (Kind=nag_wp) :: a, b, e1, e2, f, x
Integer :: ifail, maxcal
! .. Local Arrays ..
Real (Kind=nag_wp) :: ruser(1)
Integer :: iuser(1)
! .. Executable Statements ..
Write (nout,*) 'E04ABA Example Program Results'
! E1 and E2 are set to zero so that E04ABA will reset them to
! their default values
e1 = 0.0_nag_wp
e2 = 0.0_nag_wp
! The minimum is known to lie in the range (3.5, 5.0)
a = 3.5_nag_wp
b = 5.0_nag_wp
! Allow 30 calls of FUNCT
maxcal = 30
ifail = -1
Call e04aba(funct,e1,e2,a,b,maxcal,x,f,iuser,ruser,ifail)
Select Case (ifail)
Case (0,2)
Write (nout,*)
Write (nout,99999) 'The minimum lies in the interval', a, ' to', b
Write (nout,99999) 'Its estimated position is', x, ','
Write (nout,99998) 'where the function value is ', f
Write (nout,99997) maxcal, 'function evaluations were required'
End Select
99999 Format (1X,A,F11.8,A,F11.8)
99998 Format (1X,A,F7.4)
99997 Format (1X,I2,1X,A)
End Program e04abae