! D01UA_P0W_F Example Program Text
! Mark 30.1 Release. NAG Copyright 2024.
Module d01ua_p0w_fe_mod
! .. Use Statements ..
Use iso_c_binding, Only: c_ptr
Use nag_library, Only: nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Accessibility Statements ..
Private
Public :: f
! .. Parameters ..
Integer, Parameter, Public :: nout = 6
Contains
Subroutine f(ad_handle,x,nx,fv,iflag,iuser,ruser)
! .. Scalar Arguments ..
Type (c_ptr), Intent (Inout) :: ad_handle
Integer, Intent (Inout) :: iflag
Integer, Intent (In) :: nx
! .. Array Arguments ..
Real (Kind=nag_wp), Intent (Out) :: fv(nx)
Real (Kind=nag_wp), Intent (Inout) :: ruser(*)
Real (Kind=nag_wp), Intent (In) :: x(nx)
Integer, Intent (Inout) :: iuser(*)
! .. Intrinsic Procedures ..
Intrinsic :: exp, log
! .. Executable Statements ..
Select Case (iuser(1))
Case (1)
fv = 4.0E0_nag_wp/(1.0E0_nag_wp+ruser(1)*x*x)
Case (2)
fv = 1.0E0_nag_wp/(x*x*log(ruser(1)*x))
Case (3)
fv = exp(-ruser(1)*x)/x
Case (4)
fv = ruser(1)/x
Case (5)
fv = exp(-3.0E0_nag_wp*ruser(1)*x*x-4.0E0_nag_wp*x-1.0E0_nag_wp)
Case (6)
fv = exp(2.0E0_nag_wp*ruser(1)*x+2.0E0_nag_wp)
Case Default
iflag = -1
End Select
Return
End Subroutine f
End Module d01ua_p0w_fe_mod
Program d01ua_p0w_fe
! D01UA_P0W_F Example Main Program
! .. Use Statements ..
Use d01ua_p0w_fe_mod, Only: f, nout
Use iso_c_binding, Only: c_ptr
Use nagad_library, Only: d01ua_p0w_f
Use nag_library, Only: nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Local Scalars ..
Type (c_ptr) :: ad_handle
Real (Kind=nag_wp) :: a, b, dinest
Integer :: funid, ifail, key, n
! .. Local Arrays ..
Real (Kind=nag_wp) :: ruser(1)
Integer :: iuser(1)
! .. Executable Statements ..
Write (nout,*) 'D01UA_P0W_F Example Program Results'
n = 64
ruser(1) = 1.0_nag_wp
cases: Do funid = 1, 6
Write (nout,*)
Select Case (funid)
Case (1)
Write (nout,*) 'Gauss-Legendre example'
a = 0.0_nag_wp
b = 1.0_nag_wp
key = 0
Case (2)
Write (nout,*) 'Rational Gauss example'
a = 2.0_nag_wp
b = 0.0_nag_wp
key = -5
Case (3)
Write (nout,*) 'Gauss-Laguerre example (adjusted weights)'
a = 2.0_nag_wp
b = 1.0_nag_wp
key = -3
Case (4)
Write (nout,*) 'Gauss-Laguerre example (normal weights)'
a = 2.0_nag_wp
b = 1.0_nag_wp
key = 3
Case (5)
Write (nout,*) 'Gauss-Hermite example (adjusted weights)'
a = -1.0_nag_wp
b = 3.0_nag_wp
key = -4
Case (6)
Write (nout,*) 'Gauss-Hermite example (normal weights)'
a = -1.0_nag_wp
b = 3.0_nag_wp
key = 4
End Select
iuser(1) = funid
! Call the passive routine
ifail = 0
Call d01ua_p0w_f(ad_handle,key,a,b,n,f,dinest,iuser,ruser,ifail)
Write (nout,*)
Write (nout,99999) 'dinest =', dinest
99999 Format (1X,A,1X,F10.5)
End Do cases
End Program d01ua_p0w_fe