!*****************************************************************
!*    Test program for cubature over rectangles using  Gauss     *
!*                                                               *
!* ------------------------------------------------------------- *
!* SAMPLE RUN:                                                   *
!* (Integrate function EXP(-(x*x + y*y)) in rectangle defined by *
!*  x1=0, x2=10, y1=0, y2=10).                                   *
!*                                                               *
!* ------------------------------------------------------        * 
!*   #      Error     Value          Error      Function         *
!* Method   code     Integral      Estimation     calls          *
!* ------------------------------------------------------        *
!*   0      ( 0)    0.27460788                      16           *
!*   1      ( 0)    0.94345609                      64           *
!*   2      ( 0)    0.77390367                     144           *
!*   3      ( 0)    0.78537787                     256           *
!*   4      ( 0)    0.78547216                     400           *
!*   5      ( 0)    0.78539063                     576           *
!*   6      ( 0)    0.78539862                     784           *
!*   7      ( 0)    0.78539814                    1024           *
!*   0      ( 0)    0.77973416    0.168375E+00      80           *
!*   1      ( 0)    0.78676409   -0.522307E-01     320           * 
!*   2      ( 0)    0.78527076    0.378903E-02     720           *
!*   3      ( 0)    0.78540422    0.878258E-05    1280           *
!*   4      ( 0)    0.78539799   -0.247227E-04    2000           *
!*   5      ( 0)    0.78539817    0.251254E-05    2880           * 
!*   6      ( 0)    0.78539816   -0.151354E-06    3920           *
!*   7      ( 0)    0.78539816    0.626142E-08    5120           *
!* ------------------------------------------------------        *
!*                                                               *
!* ------------------------------------------------------------- *
!* Reference:                                                    *
!* "Numerical Algorithms with C, By Gisela Engeln-Muellges       *
!*  and Frank Uhlig, Springer-Verlag, 1996" [BIBLI 11].          *
!*                                                               *
!*                         F90 Release 1.0 By J-P Moreau, Paris. *
!*                                  (www.jpmoreau.fr)            *
!*****************************************************************
Program TK4GAU

implicit none

  real*8 a, b, c, d, W, F
  integer Nx, Ny, i, Verfahren
  integer mSCH                          !<>0: with eror estimate
  integer ncalls
  integer Kub4GauE

  Nx = 4; Ny = 4
  a = 0.d0; c = 0.d0
  b = 10.d0; d = 10.d0

  print *,' -------------------------------------------------------'
  print *,'   #      Error     Value          Error       Function '
  print *,' Method   code     Integral      Estimation      calls  '
  print *,' -------------------------------------------------------'

  do mSCH = 0, 1
    do Verfahren = 0, 7
     
      ncalls = 0

      i = Kub4GauE(a, b, Nx, c, d, Ny, Verfahren, W, mSCH, F, ncalls)

      if (mSCH.ne.0) then
        write(*,10) Verfahren, i, W, F, ncalls
      else
        write(*,20) Verfahren, i, W, ncalls 
      end if
    end do
  end do
  print *,' -------------------------------------------------------'
  stop

10 format(I5,'      (',I2,')  ',F12.8,'   ',e13.6,'     ',I4)
20 format(I5,'      (',I2,')  ',F12.8,'                     ',I4)

END

!user defined function(x,y) to integrate
real*8 Function func(x,y)
implicit none
real*8 x,y
  func = Exp(-(x*x+y*y))
return
end

!end of file tk4gau.f90