`Grid`#

class acoular.grids.Grid

Bases: ABCHasStrictTraits

Abstract base class for grid geometries.

This class defines a common interface for all grid geometries and provides tools to query grid properties and related data. It is intended to serve as a base class for specialized grid implementations and should not be instantiated directly as it lacks concrete functionality.

Unit of length

The source code is agnostic to the unit of length. The positions’ coordinates are assumed to be in meters. This is consistent with the standard Environment class which uses the speed of sound at 20°C at sea level under standard atmosphere pressure in m/s. If the positions’ coordinates are provided in a unit other than meter, it is advisable to change the c attribute to match the given unit.

size = Property(): The total number of grid points. This property is automatically calculated based on other defining attributes of the grid. (read-only)

shape = Property(): The shape of the grid, represented as a tuple. Primarily useful for Cartesian grids. (read-only)

pos = Property(): The grid positions represented as a (3, size) array of floats. (read-only) All positions’ coordinates are in meters by default (see here).

digest = Property: A unique identifier for the grid, based on its properties. (read-only)

subdomain(sector)

Return the indices for a subdomain in the grid.

Allows arbitrary subdomains of type Sector.

Parameters:

sectorSector object: Sector describing the subdomain.

Returns:

tuple: A 2-tuple of arrays of integers or numpy.s_ objects that can be used to mask or select the specified subdomain from a grid-shaped array.

Notes

The numpy.where() method is used to determine the the indices.

export_gpos(filename)

Export the grid positions to an XML file.

This method generates an XML file containing the positions of all grid points. Each point is represented by a <pos> element with Name, x, y, and z attributes. The generated XML is formatted to match the structure required for importing into the ImportGrid class.

Parameters:

filenamestr: The path to the file to which the grid positions will be written. The file extension must be .xml.

Raises:

OSError: If the file cannot be written due to permissions issues or invalid file paths.

Notes

The file will be saved in UTF-8 encoding.
The Name attribute for each point is set as "Point {i+1}", where i is the index of the grid point.
If subgrids are defined, they will be included as the subgrid attribute.

Examples

Export a grid with 100 points to an XML file:

>>> import acoular as ac
>>> import numpy as np
>>> grid = ac.ImportGrid()
>>> # Create some grid points
>>> points = np.arange(9).reshape(3, 3)
>>> grid.pos = points
>>> grid.export_gpos('grid_points.xml')

The generated grid_points.xml file will look like this:

<?xml version="1.1" encoding="utf-8"?><Grid name="grid_points">
  <pos Name="Point 1" x="0" y="1" z="2"/>
  <pos Name="Point 2" x="3" y="4" z="5"/>
  <pos Name="Point 3" x="6" y="7" z="8"/>
</Grid>

Grid#

`Grid`#