`LineGrid`#

class acoular.grids.LineGrid

Bases: Grid

Define a 3D grid for a line geometry.

The LineGrid class represents a grid where points are arranged linearly in 3D space. The grid is defined by a starting location (loc), a direction vector (direction), a total length (length), and the number of points (num_points) along the line.

Notes

The distance between points is length / ( num_points - 1).
The direction vector is normalized to ensure consistency.

Examples

Create a line grid with 5 points along the x-axis, starting at (0, 0, 0), with a length of 4 meters:

>>> import acoular as ac
>>> grid = ac.LineGrid()
>>> grid.loc = (0.0, 0.0, 0.0)
>>> grid.direction = (1.0, 0.0, 0.0)
>>> grid.length = 4
>>> grid.num_points = 5
>>> grid.pos
array([[0., 1., 2., 3., 4.],
       [0., 0., 0., 0., 0.],
       [0., 0., 0., 0., 0.]])

loc: Starting point of the grid in 3D space. Default is (0.0, 0.0, 0.0).

direction: A vector defining the orientation of the line in 3D space. Default is (1.0, 0.0, 0.0).

length: Total length of the line. Default is 1.0.

num_points: Number of grid points along the line. Default is 1.

size: The total number of grid points. Automatically updated when other grid-defining attributes are set. (read-only)

pos: A (3, size) array containing the x, y, and z positions of the grid points. (read-only) All positions’ coordinates are in meters by default (see here).

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

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>

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.

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

LineGrid#

`LineGrid`#