triqs::lattice::grid_generator

#include <triqs/lattice/grid_generator.hpp>

Detailed Description

Forward iterator generating uniformly-spaced points in the d-dimensional unit cube \( [0,1)^d \).

For a given dimension \( d \in \{1,2,3\} \) and a number of points \( n \) per dimension, the generator iterates over the cuboid grid of \( n^d \) points

\[ \mathbf{p}_{(i_1,\dots,i_d)} = \left( \frac{i_1 + 1/2}{n}, \dots, \frac{i_d + 1/2}{n} \right) , \quad i_k \in \{0,\dots,n-1\} \; , \]

i.e. each point is shifted by half a step away from the cuboid faces so that the grid lies strictly inside the open unit cube. The iteration order is x (fastest), then y, then z (slowest).

The generated points are always 3-dimensional. For \( d < 3 \) the trailing coordinates are kept at their half-step value \( 1/2 \).

Typical usage in C++ is via the implicit bool conversion and the increment operator inherited from itertools::iterator_facade:

for (auto gen = grid_generator{3, 10}; gen; ++gen) {
  nda::vector<double> const& k = *gen;
  // ... use k ...
}

Definition at line 66 of file grid_generator.hpp.

Public Member Functions
	grid_generator ()
	Default constructor: produces a 3-dimensional generator with zero points (an empty/end iterator).
	grid_generator (int dim, int nkpts)
	Construct a grid generator with the given dimension and number of points per dimension.
int	index () const
	Linear index of the current grid point in the iteration order (x fastest, then y, then z).
	operator bool () const
	Implicit conversion to bool: true while the generator has not yet been exhausted.
bool	operator== (grid_generator const &other) const
	Equal-to comparison: two generators are equal if they share the same dimension, number of points and index.
int	size () const
	Total number of grid points, equal to \( N_X \cdot N_Y \cdot N_Z \) (trailing factors are 1 for dim < 3).

Constructor & Destructor Documentation

grid_generator()

triqs::lattice::grid_generator::grid_generator ( int dim, int nkpts )

inline

Construct a grid generator with the given dimension and number of points per dimension.

Parameters

dim	Dimension of the grid (1, 2 or 3).
nkpts	Number of points along each dimension.

Definition at line 119 of file grid_generator.hpp.

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The documentation for this class was generated from the following file:

• triqs/lattice/grid_generator.hpp