CoordinateTransformer#

Class Methods

CoordinateTransformer.from_pipeline(...)

Create a transformer from a PROJ pipeline definition.

CoordinateTransformer.from_crs(crs_s, crs_t)

Create a coordinate transformer from source CRS to target CRS.

Methods

CoordinateTransformer.is_3d(coo)

Return whether the coordinate array has a Z component.

CoordinateTransformer.transform(coordinates)

Transform coordinates using the configured transformer chain.

Properties

CoordinateTransformer.source_crs

Return the source CRS of the transformer chain.

CoordinateTransformer.target_crs

Return the target CRS of the transformer chain.
class weitsicht.CoordinateTransformer(transformer: Transformer)[source]#
class weitsicht.CoordinateTransformer(transformer: list[Transformer])

Bases: object

Class to handle transformations of coordinates. Basically a little pyproj wrapper with basic functions needed in the package.

Parameters:

transformer (Transformer | list[Transformer])

__init__(transformer: Transformer)[source]#
__init__(transformer: list[Transformer])

Create a transformer wrapper.

Parameters:

transformer (Transformer | list[Transformer]) – A single pyproj transformer or a chain of transformers.

property source_crs: CRS | None#

Return the source CRS of the transformer chain.

property target_crs: CRS | None#

Return the target CRS of the transformer chain.

classmethod from_pipeline(proj_pipeline: str)[source]#

Create a transformer from a PROJ pipeline definition.

Parameters:

proj_pipeline (str) – PROJ pipeline string.

Returns:

Transformer instance.

Return type:

CoordinateTransformer

Raises:

CoordinateTransformationError – If the pipeline cannot be established.

classmethod from_crs(crs_s: CRS | None, crs_t: CRS | None) → CoordinateTransformer | None[source]#

Create a coordinate transformer from source CRS to target CRS.

If both CRSs are None or equal, this returns None (no transformation required).

Parameters:

  • crs_s (CRS | None) – Source CRS, or None.

  • crs_t (CRS | None) – Target CRS, or None.

Returns:

Coordinate transformer or None if no transformation is required.

Return type:

CoordinateTransformer | None

Raises:
static is_3d(coo: ArrayNx2 | ArrayNx3)[source]#

Return whether the coordinate array has a Z component.

Parameters:

coo (ArrayNx2 | ArrayNx3) – Coordinate array.

Returns:

True if the input has shape N×3.

Return type:

bool

transform(coordinates: ArrayNx3 | ArrayNx2, direction: str = 'forward') → ArrayNx3 | ArrayNx2[source]#

Transform coordinates using the configured transformer chain.

Parameters:

  • coordinates (ArrayNx3 | ArrayNx2) – Coordinates to transform as N×2 (2D) or N×3 (3D).

  • direction (str) – Transform direction (forward, inverse, identity), defaults to forward.

Returns:

Transformed coordinates with the same dimensionality as input.

Return type:

ArrayNx3 | ArrayNx2

Raises:

CoordinateTransformationError – If input dimensions are invalid or a transformation fails.

transform_vector(coordinates_start: ArrayNx3, vector: ArrayNx3, direction: str = 'forward') → ArrayNx3[source]#

Transform direction vectors using the configured transformer chain.

Vectors can not be transformed directly through most CRS transformations, therefore this helper transforms two points per vector and derives the resulting direction: start and start + unit(vector) * 10 (i.e. 10 units along the provided vector direction).

Parameters:

  • coordinates_start (ArrayNx3) – Start coordinates (N×3).

  • vector (ArrayNx3) – Direction vectors in the source CRS (N×3 or single 3-vector).

  • direction (str) – Transform direction (forward, inverse, identity), defaults to forward.

Returns:

Unit direction vectors in the target CRS (N×3).

Return type:

ArrayNx3

Raises:

  • ValueError – If input shapes are incompatible or vectors have zero length.

  • CoordinateTransformationError – If transforming coordinates fails.