00001 subroutine poisson_solver_AHfinder(sou,pot)
00002 use phys_constant, only : long, pi
00003 use grid_parameter, only : nlg, npg, ntg
00004 use legendre_fn_grav, only : plmg, hplmg, facnmg, epsig
00005 use trigonometry_grav_theta
00006 use trigonometry_grav_phi, only : sinmpg, cosmpg, hsinmpg, hcosmpg
00007 use weight_midpoint_grav, only : hwdtg, hwdpg
00008 use make_array_2d
00009 implicit none
00010 integer :: im, il, nlgtmp
00011 integer :: it, itt, ip, ipp
00012 real(long) :: pef, wok, pi4inv, ell, facl
00013 real(long), pointer :: sou(:,:), pot(:,:)
00014 real(long), pointer :: work1c(:,:), work2c(:,:), work4c(:,:),
00015 work1s(:,:), work2s(:,:), work4s(:,:)
00016
00017 call alloc_array2d(work1c, 1, ntg, 0, nlg)
00018 call alloc_array2d(work1s, 1, ntg, 0, nlg)
00019 call alloc_array2d(work2c, 0, nlg, 0, nlg)
00020 call alloc_array2d(work2s, 0, nlg, 0, nlg)
00021 call alloc_array2d(work4c, 0, nlg, 0, ntg)
00022 call alloc_array2d(work4s, 0, nlg, 0, ntg)
00023
00024 work1c = 0.0d0
00025 work1s = 0.0d0
00026 do im = 0, nlg
00027 do itt = 1, ntg
00028 do ipp = 1, npg
00029 wok = hwdtg(itt)*hwdpg(ipp)*sou(itt,ipp)
00030 work1c(itt,im) = work1c(itt,im) + wok*hcosmpg(im,ipp)
00031 work1s(itt,im) = work1s(itt,im) + wok*hsinmpg(im,ipp)
00032 end do
00033 end do
00034 end do
00035
00036 work2c = 0.0d0
00037 work2s = 0.0d0
00038 do il = 0, nlg
00039 do im = 0, nlg
00040 pef = epsig(im)*facnmg(il,im)
00041 do itt = 1, ntg
00042 wok = pef*hplmg(il,im,itt)
00043 work2c(il,im) = work2c(il,im) + wok*work1c(itt,im)
00044 work2s(il,im) = work2s(il,im) + wok*work1s(itt,im)
00045 end do
00046 end do
00047 end do
00048
00049 work4c = 0.0d0
00050 work4s = 0.0d0
00051 do it = 0, ntg
00052 do im = 0, nlg
00053 do il = 0, nlg
00054 ell = dble(il)
00055 facl = (2.0d0*ell+1.0d0)/(ell*(ell+1.0d0)+2.0d0)
00056 wok = plmg(il,im,it)*facl
00057 work4c(im,it) = work4c(im,it) + wok*work2c(il,im)
00058 work4s(im,it) = work4s(im,it) + wok*work2s(il,im)
00059 end do
00060 end do
00061 end do
00062
00063 pot = 0.0d0
00064 do ip = 0, npg
00065 do it = 0, ntg
00066 do im = 0, nlg
00067 pot(it,ip) = pot(it,ip)&
00068 & + work4c(im,it)*cosmpg(im,ip) &
00069 & + work4s(im,it)*sinmpg(im,ip)
00070 end do
00071 end do
00072 end do
00073
00074 pi4inv = 1.0d0/4.0d0/pi
00075 pot(0:ntg,0:npg) = - pi4inv*pot(0:ntg,0:npg)
00076
00077 end subroutine poisson_solver_AHfinder