Contains functions to solve Poisson's equation for self-gravity in 1D, 2D and 3D using FFTs (actually, the 1D algorithm uses Forward Elimination followed by Back Substitution: FEBS). More...
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Functions | |
| void | selfg_fft_1d (DomainS *pD) |
| This algorithm taken from pp.35-38 of Hockney & Eastwood. | |
| void | selfg_fft_2d (DomainS *pD) |
| Only works for uniform grid, periodic boundary conditions. | |
| void | selfg_fft_3d (DomainS *pD) |
| Only works for uniform grid, periodic boundary conditions. | |
| void | selfg_fft_2d_init (MeshS *pM) |
| Initializes plans for forward/backward FFTs, and allocates memory needed by FFTW. | |
| void | selfg_fft_3d_init (MeshS *pM) |
| Initializes plans for forward/backward FFTs, and allocates memory needed by FFTW. | |
Variables | |
| static struct ath_2d_fft_plan * | fplan2d |
| static struct ath_2d_fft_plan * | bplan2d |
| static struct ath_3d_fft_plan * | fplan3d |
| static struct ath_3d_fft_plan * | bplan3d |
| static ath_fft_data * | work = NULL |
Detailed Description
Contains functions to solve Poisson's equation for self-gravity in 1D, 2D and 3D using FFTs (actually, the 1D algorithm uses Forward Elimination followed by Back Substitution: FEBS).
These functions require PERIODIC BCs and use the Jeans swindle.
The 2D and 3D f'ns use FFTW3.x, and for MPI parallel use Steve Plimpton's block decomposition routines added by N. Lemaster to /athena/fftsrc. This means to use these fns the code must be
- (1) configured with --with-gravity=fft --enable-fft
- (2) compiled with links to FFTW libraries (may need to edit Makeoptions)
For NON-PERIODIC BCs, use selfg_multig() functions.
CONTAINS PUBLIC FUNCTIONS:
- selfg_fft_1d() - actually uses FEBS
- selfg_fft_2d() - 2D Poisson solver using FFTs
- selfg_fft_3d() - 3D Poisson solver using FFTs
- selfg_fft_2d_init() - initializes FFT plans for 2D
- selfg_fft_3d_init() - initializes FFT plans for 3D
Definition in file selfg_fft.c.
Function Documentation
| void selfg_fft_1d | ( | DomainS * | pD | ) |
This algorithm taken from pp.35-38 of Hockney & Eastwood.
Actually uses forward elimination - back substituion!! Only works for uniform grid, periodic boundary conditions
Definition at line 57 of file selfg_fft.c.
References ConsS::d, GridS::dx1, four_pi_G, grav_mean_rho, DomainS::Grid, GridS::ie, GridS::is, GridS::js, GridS::ks, GridS::Nx, GridS::Phi, GridS::Phi_old, and GridS::U.
| void selfg_fft_2d | ( | DomainS * | pD | ) |
Only works for uniform grid, periodic boundary conditions.
Definition at line 105 of file selfg_fft.c.
References ath_2d_fft(), ConsS::d, GridS::Disp, dkx, GridS::dx1, GridS::dx2, four_pi_G, ath_2d_fft_plan::gcnt, grav_mean_rho, DomainS::Grid, GridS::ie, GridS::is, GridS::je, GridS::js, GridS::ks, DomainS::Nx, GridS::Nx, GridS::Phi, GridS::Phi_old, GridS::U, and work.
| void selfg_fft_2d_init | ( | MeshS * | pM | ) |
Initializes plans for forward/backward FFTs, and allocates memory needed by FFTW.
Definition at line 289 of file selfg_fft.c.
References ath_2d_fft_malloc(), ath_2d_fft_quick_plan(), ATH_FFT_BACKWARD, ATH_FFT_FORWARD, MeshS::Domain, MeshS::DomainsPerLevel, DomainS::Grid, MeshS::NLevels, and work.
Referenced by selfg_init().
| void selfg_fft_3d | ( | DomainS * | pD | ) |
Only works for uniform grid, periodic boundary conditions.
Definition at line 186 of file selfg_fft.c.
References ath_3d_fft(), ConsS::d, GridS::Disp, dkx, GridS::dx1, GridS::dx2, GridS::dx3, four_pi_G, ath_3d_fft_plan::gcnt, grav_mean_rho, DomainS::Grid, GridS::ie, GridS::is, GridS::je, GridS::js, GridS::ke, GridS::ks, DomainS::Nx, GridS::Nx, GridS::Phi, GridS::Phi_old, GridS::U, and work.
| void selfg_fft_3d_init | ( | MeshS * | pM | ) |
Initializes plans for forward/backward FFTs, and allocates memory needed by FFTW.
NOTE: for SMR, allocation of memory for Poisson kernel arrays Geee, Gooo, Goee, Geoo, Geoe, Goeo, Geeo, Gooe could also be done here
Definition at line 311 of file selfg_fft.c.
References ath_3d_fft_malloc(), ath_3d_fft_quick_plan(), ATH_FFT_BACKWARD, ATH_FFT_FORWARD, MeshS::Domain, MeshS::DomainsPerLevel, DomainS::Grid, MeshS::NLevels, and work.
Variable Documentation
struct ath_2d_fft_plan * bplan2d [static] |
Definition at line 41 of file selfg_fft.c.
struct ath_3d_fft_plan * bplan3d [static] |
Definition at line 42 of file selfg_fft.c.
struct ath_2d_fft_plan* fplan2d [static] |
Definition at line 41 of file selfg_fft.c.
struct ath_3d_fft_plan* fplan3d [static] |
Definition at line 42 of file selfg_fft.c.
ath_fft_data* work = NULL [static] |
Definition at line 43 of file selfg_fft.c.
Referenced by selfg_fft_2d(), selfg_fft_2d_init(), selfg_fft_3d(), and selfg_fft_3d_init().
