spatial.GeometryFM3D

spatial.GeometryFM3D(
    self,
    *,
    node_coordinates,
    element_table,
    codes=None,
    projection='LONG/LAT',
    dfsu_type=DfsuFileType.Dfsu3DSigma,
    element_ids=None,
    node_ids=None,
    n_layers=1,
    n_sigma=None,
    validate=True,
    reindex=False,
)

Flexible 3d mesh geometry.

Attributes

Name	Description
bottom_elements	List of 3d element ids of bottom layer.
boundary_codes	Unique list of boundary codes.
codes	Node codes of all nodes (0=water, 1=land, 2…=open boundaries).
e2_e3_table	The 2d-to-3d element connectivity table for a 3d object.
elem2d_ids	The associated 2d element id for each 3d element.
element_coordinates	Center coordinates of each element.
is_geo	Are coordinates geographical (LONG/LAT)?
is_local_coordinates	Are coordinates relative (NON-UTM)?
layer_ids	The layer number (0=bottom, 1, 2, …) for each 3d element.
max_nodes_per_element	The maximum number of nodes for an element.
n_elements	Number of elements.
n_layers	Maximum number of layers.
n_layers_per_column	List of number of layers for each column.
n_nodes	Number of nodes.
n_sigma_layers	Number of sigma layers.
n_z_layers	Maximum number of z-layers.
projection	The projection.
projection_string	The projection string.
top_elements	List of 3d element ids of surface layer.

Methods

Name	Description
get_layer_elements	3d element ids for one (or more) specific layer(s).
get_space_axis	Get geographic space axis indices within the geometry’s dims.
reduce	Return reduced geometry after spatial aggregation.
to_2d_geometry	extract 2d geometry from 3d geometry.

get_layer_elements

spatial.GeometryFM3D.get_layer_elements(layers)

3d element ids for one (or more) specific layer(s).

Parameters

Name	Type	Description	Default
layers	int or list(int)	layer between 0 (bottom) and n_layers-1 (top) (can also be negative counting from -1 at the top layer)	required

Returns

Name	Type	Description
	np.array(int)	element ids

get_space_axis

spatial.GeometryFM3D.get_space_axis()

Get geographic space axis indices within the geometry’s dims.

Returns which of the geometry’s dims represent geographic space dimensions, as opposed to spectral or other non-geographic dimensions.

This is used when axis=“space” or axis=“spatial” is specified in operations like aggregate, mean, etc.

Returns

Name	Type	Description
	tuple[int, …]	Space axis indices (0-indexed within geometry.dims). Returns empty tuple if there are no space dimensions (e.g., point geometries, pure spectral geometries).

Examples

Grid2D with dims=(“y”, “x”) returns (0, 1) - both are space. GeometryFMAreaSpectrum with dims=(“element”, “direction”, “frequency”) returns (0,) - only element is space, direction/frequency are spectral. GeometryFMPointSpectrum with dims=(“frequency”,) returns () - no space.

reduce

spatial.GeometryFM3D.reduce(axis)

Return reduced geometry after spatial aggregation.

to_2d_geometry

spatial.GeometryFM3D.to_2d_geometry()

extract 2d geometry from 3d geometry.

Returns

Name	Type	Description
	GeometryFM2D	2d geometry