RectGrid3D¶

class acoular.grids.RectGrid3D¶

Bases: RectGrid

Provide a cartesian 3D grid for the beamforming results.

The grid has cubic or nearly cubic cells. It is defined by lower and upper x-, y- and z-limits.

z_min = Float(-1.0, desc='minimum z-value')¶: The lower z-limit that defines the grid. Default is -1.

z_max = Float(1.0, desc='maximum z-value')¶: The upper z-limit that defines the grid. Default is 1.

nxsteps = Property(desc='number of grid points along x-axis')¶: Number of grid points along x-axis. (read-only)

nysteps = Property(desc='number of grid points along y-axis')¶: Number of grid points along y-axis. (read-only)

nzsteps = Property(desc='number of grid points along z-axis')¶: Number of grid points along z-axis. (read-only)

increment = Property(desc='step size')¶: The cell side length for the grid. This can either be a scalar (same increments in all 3 dimensions) or a (3,) array of tuple of floats with respective increments in x-, y-, and z-direction. Default is 0.1.

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

index(x, y, z)¶

Return the indices for a grid point near a certain coordinate.

This can be used to query results or coordinates at or near a certain coordinate. Raises an exception if the given coordinate is outside the grid.

Parameters:

x, y, zfloat: The coordinates for which the indices is queried.

Returns:

3-tuple of ints: The indices that give the grid point nearest to the given x, y, z coordinates from an array with the same shape as the grid.

Examples

Check which of the points in a simple 8-point rectangular grid is closest to the point (0.5, 0.5, 1.0).

>>> import acoular as ac
>>>
>>> grid = ac.RectGrid3D()
>>> grid.increment = 2
>>> grid.pos
array([[-1., -1., -1., -1.,  1.,  1.,  1.,  1.],
       [-1., -1.,  1.,  1., -1., -1.,  1.,  1.],
       [-1.,  1., -1.,  1., -1.,  1., -1.,  1.]])
>>>
>>> grid.index(0.5, 0.5, 1.0)
(1, 1, 1)

indices(x1, y1, z1, x2, y2, z2)¶

Return the indices for a subdomain in the grid.

Allows box-shaped subdomains. This can be used to mask or to query results from a certain sector or subdomain.

Parameters:

x1, y1, z1, x2, y2, z2float: A box-shaped sector is assumed that is given by two corners (x1,y1,z1) and (x2,y2,z2).

Returns:

3-tuple of numpy.s_ objects: The indices that can be used to mask/select the grid subdomain from an array with the same shape as the grid.

Examples

Get the indices of the grid points of a simple 27-point rectangular grid which are located inside the first octant.

>>> import acoular as ac
>>>
>>> grid = ac.RectGrid3D()
>>> grid.increment = 1
>>> grid.pos
array([[-1., -1., -1., -1., -1., -1., -1., -1., -1.,  0.,  0.,  0.,  0.,
         0.,  0.,  0.,  0.,  0.,  1.,  1.,  1.,  1.,  1.,  1.,  1.,  1.,
         1.],
       [-1., -1., -1.,  0.,  0.,  0.,  1.,  1.,  1., -1., -1., -1.,  0.,
         0.,  0.,  1.,  1.,  1., -1., -1., -1.,  0.,  0.,  0.,  1.,  1.,
         1.],
       [-1.,  0.,  1., -1.,  0.,  1., -1.,  0.,  1., -1.,  0.,  1., -1.,
         0.,  1., -1.,  0.,  1., -1.,  0.,  1., -1.,  0.,  1., -1.,  0.,
         1.]])
>>>
>>> grid.indices(0, 0, 0, 1, 1, 1)
(slice(1, 3, None), slice(1, 3, None), slice(1, 3, None))

Acoular 25.03 documentation

RectGrid3D

RectGrid3D¶