cartagen.propagation_crow_flies

propagation_crow_flies(objects, initiator_start, initiator_end, frozen_objects, distance, interval=2.0)

Propagate a displacement using the method “as the crow flies”.

Implementation of the displacement propagation algorithm “as the crow flies”, by Legrand et al. [1]. This function propagates the displacement defined by the movement of initiator objects to nearby movable objects, while respecting frozen objects that should not be moved.

Be careful, the initiators should be LineString, not MultiLineString objects.

Parameters:

• objects (GeoDataFrame of Point or LineString) – The objects modified by the propagation.

• initiator_start (LineString) – The origin of the propagation before displacement.

• initiator_end (LineString) – The origin of the propagation after displacement.

• frozen (GeoDataFrame of Point or LineString) – The objects that should not be modified by the propagation.

• distance (float) – The distance around the initiator to propagate displacement. It corresponds to SizePZ in the paper by Legrand et al.

• interval (float, optional) – Interval used for the interpolation during the initial displacement vector calculation.

Returns:

GeoDataFrame – Same as input but with displaced geometries

Warning

Be careful, the initiators should be LineString, and not MultiLineString.

See also

propagation_network

Propagate a displacement along the network.

References

[1]

Cristel Legrand, Cécile Duchêne, and François Lecordix. Propagation of the displacements and deformations during a generalisation process. In International Cartographic Conference. La Coruña, Spain, 2005. ICA. event-place: La Coruña, Spain.

(Source code)