The simplest implementation of aRealMPITopology3d. More...

Inheritance diagram for dg::RealMPIGrid3d< real_type >:

Public Member Functions
	RealMPIGrid3d (real_type x0, real_type x1, real_type y0, real_type y1, real_type z0, real_type z1, unsigned n, unsigned Nx, unsigned Ny, unsigned Nz, MPI_Comm comm)
	Equal polynomial coefficients. More...

	RealMPIGrid3d (real_type x0, real_type x1, real_type y0, real_type y1, real_type z0, real_type z1, unsigned n, unsigned Nx, unsigned Ny, unsigned Nz, bc bcx, bc bcy, bc bcz, MPI_Comm comm)
	Equal polynomial coefficients. More...

	RealMPIGrid3d (RealGrid1d< real_type > gx, RealGrid1d< real_type > gy, RealGrid1d< real_type > gz, MPI_Comm comm)
	Construct a 3d topology as the product of three 1d grids. More...

	RealMPIGrid3d (const aRealMPITopology3d< real_type > &src)

Public Member Functions inherited from dg::aRealMPITopology3d< real_type >
real_type	x0 () const
	Return global x0. More...

real_type	x1 () const
	Return global x1. More...

real_type	y0 () const
	Return global y0. More...

real_type	y1 () const
	Return global y1. More...

real_type	z0 () const
	Return global z0. More...

real_type	z1 () const
	Return global z1. More...

real_type	lx () const
	Return global lx. More...

real_type	ly () const
	Return global ly. More...

real_type	lz () const
	Return global lz. More...

real_type	hx () const
	Return global hx. More...

real_type	hy () const
	Return global hy. More...

real_type	hz () const
	Return global hz. More...

unsigned	n () const
	Return n. More...

unsigned	nx () const
	number of polynomial coefficients in x More...

unsigned	ny () const
	number of polynomial coefficients in y More...

unsigned	nz () const
	number of polynomial coefficients in z More...

unsigned	Nx () const
	Return the global number of cells. More...

unsigned	Ny () const
	Return the global number of cells. More...

unsigned	Nz () const
	Return the global number of cells. More...

bc	bcx () const
	global x boundary More...

bc	bcy () const
	global y boundary More...

bc	bcz () const
	global z boundary More...

MPI_Comm	communicator () const
	Return mpi cartesian communicator that is used in this grid. More...

MPI_Comm	get_perp_comm () const
	MPI Cartesian communicator in the first two dimensions (x and y) More...

const DLT< real_type > &	dlt () const
	The Discrete Legendre Transformation. More...

const DLT< real_type > &	dltx () const

const DLT< real_type > &	dlty () const

const DLT< real_type > &	dltz () const

unsigned	size () const
	The total global number of points. More...

unsigned	local_size () const
	The total local number of points. More...

void	display (std::ostream &os=std::cout) const
	Display global and local grid paramters. More...

int	pidOf (real_type x, real_type y, real_type z) const
	Returns the pid of the process that holds the local grid surrounding the given point. More...

void	multiplyCellNumbers (real_type fx, real_type fy)
	Multiply the number of cells with a given factor. More...

void	set (unsigned new_n, unsigned new_Nx, unsigned new_Ny, unsigned new_Nz)
	Set the number of polynomials and cells. More...

void	set (unsigned new_nx, unsigned new_Nx, unsigned new_ny, unsigned new_Ny, unsigned new_nz, unsigned new_Nz)
	Set the number of polynomials and cells. More...

bool	local2globalIdx (int localIdx, int PID, int &globalIdx) const
	Map a local index plus the PID to a global vector index. More...

bool	global2localIdx (int globalIdx, int &localIdx, int &PID) const
	Map a global vector index to a local vector Index and the corresponding PID. More...

const RealGrid3d< real_type > &	local () const
	Return a non-MPI grid local for the calling process. More...

const RealGrid3d< real_type > &	global () const
	Return the global non-MPI grid. More...

Additional Inherited Members
Public Types inherited from dg::aRealMPITopology3d< real_type >
using	value_type = real_type

using	host_vector = MPI_Vector< thrust::host_vector< real_type > >
	The host vector type used by host functions like evaluate. More...

using	host_grid = RealMPIGrid3d< real_type >

Protected Member Functions inherited from dg::aRealMPITopology3d< real_type >
	~aRealMPITopology3d ()=default
	disallow deletion through base class pointer More...

	aRealMPITopology3d (RealGrid1d< real_type > gx, RealGrid1d< real_type > gy, RealGrid1d< real_type > gz, MPI_Comm comm)
	Construct a 3d topology as the product of three 1d grids. More...

	aRealMPITopology3d (const aRealMPITopology3d &src)=default

aRealMPITopology3d &	operator= (const aRealMPITopology3d &src)=default

virtual void	do_set (unsigned new_nx, unsigned new_Nx, unsigned new_ny, unsigned new_Ny, unsigned new_nz, unsigned new_Nz)=0

Detailed Description

template<class real_type>
struct dg::RealMPIGrid3d< real_type >

The simplest implementation of aRealMPITopology3d.

This code snippet demonstrates how to discretize and compute the norm of a function

// define the function to integrate
double function(double x, double y, double z, double amp){
    return amp*exp(x)*exp(y)*exp(z);
}
 
// create a grid of the domain [0,2]x[0,2]x[0,2] with 20 cells in x, y and z and 3 polynomial coefficients and x and y and 1 in z
//... use MPI_Cart_create to create 3d Cartesian communicator
dg::MPIGrid3d g3d( 0, 2, 0, 2, 0, 2, 3, 20, 20, 20, comm3d);
 
// create the Gaussian weights (volume form) for the integration
const dg::MHVec w3d = dg::create::weights( g3d);
 
// our function needs to depend only on x, y and z so let's fix the amplitude to 2
using namespace std::placeholders; //for _1, _2, _3
auto functor = std::bind( function, _1, _2, _3, 2.);
 
// discretize the function on the grid
const dg::MHVec vec = dg::evaluate( functor, g3d);
 
// now compute the scalar product (the L2 norm)
double norm = dg::blas2::dot(vec, w3d, vec);
 
// norm is now: (exp(4)-exp(0))^3/2

Constructor & Destructor Documentation

◆ RealMPIGrid3d() [1/4]

template<class real_type >

dg::RealMPIGrid3d< real_type >::RealMPIGrid3d	(	real_type	x0,
		real_type	x1,
		real_type	y0,
		real_type	y1,
		real_type	z0,
		real_type	z1,
		unsigned	n,
		unsigned	Nx,
		unsigned	Ny,
		unsigned	Nz,
		MPI_Comm	comm
	)

inline

Equal polynomial coefficients.

Parameters

x0	left boundary in x
x1	right boundary in x
y0	lower boundary in y
y1	upper boundary in y
z0	lower boundary in z
z1	upper boundary in z
n	# of polynomial coefficients for x and y dimension ( z-direction is set to 1) (1<=n<=20)
Nx	# of points in x
Ny	# of points in y
Nz	# of points in z
comm	a three-dimensional Cartesian communicator

Note: the paramateres given in the constructor are global parameters

◆ RealMPIGrid3d() [2/4]

template<class real_type >

dg::RealMPIGrid3d< real_type >::RealMPIGrid3d	(	real_type	x0,
		real_type	x1,
		real_type	y0,
		real_type	y1,
		real_type	z0,
		real_type	z1,
		unsigned	n,
		unsigned	Nx,
		unsigned	Ny,
		unsigned	Nz,
		bc	bcx,
		bc	bcy,
		bc	bcz,
		MPI_Comm	comm
	)

inline

Equal polynomial coefficients.

Parameters

x0	left boundary in x
x1	right boundary in x
y0	lower boundary in y
y1	upper boundary in y
z0	lower boundary in z
z1	upper boundary in z
n	# of polynomial coefficients for x and y dimension ( z-direction is set to 1) (1<=n<=20)
Nx	# of points in x
Ny	# of points in y
Nz	# of points in z
bcx	boundary condition in x
bcy	boundary condition in y
bcz	boundary condition in z
comm	a three-dimensional Cartesian communicator