# pygplates.ResolvedTopologicalSharedSubSegment¶

class pygplates.ResolvedTopologicalSharedSubSegment

Bases: Boost.Python.instance

The shared subset of vertices of a reconstructed topological section that uniquely contribute to the boundaries of one or more resolved topologies.

Note

Only ResolvedTopologicalBoundary and ResolvedTopologicalNetwork have boundaries and hence will share ResolvedTopologicalSharedSubSegment instances.
ResolvedTopologicalLine is excluded since it does not have a boundary.

The resolve_topologies() function can be used to generate resolved topology boundaries (ResolvedTopologicalBoundary and ResolvedTopologicalNetwork) and the shared ResolvedTopologicalSharedSubSegment instances.

Note

Each ResolvedTopologicalSharedSubSegment instance can be shared by one or more resolved topologies.
In contrast, a ResolvedTopologicalSubSegment instance belongs to a single resolved topology.
__init__()

Raises an exception This class cannot be instantiated from Python

Methods

 __init__ Raises an exception This class cannot be instantiated from Python get_feature() Same as get_topological_section_feature(). get_geometry() Same as get_resolved_geometry(). get_overriding_and_subducting_plates(…) Returns the overriding and subducting plates at this subduction zone. get_resolved_feature() Returns a feature containing the resolved sub-segment geometry. get_resolved_geometry() Returns the geometry containing the shared sub-segment vertices. get_sharing_resolved_topologies() Returns a list of resolved topologies sharing this sub-segment. get_sharing_resolved_topology_geometry_reversal_flags() Returns a list of flags indicating whether a copy of the sub-segment geometry was reversed when contributing to each resolved topology sharing this sub-segment. get_sub_segments() If this sub-segment is from a topological line section then return the child sub-segments of the topological line contributing to this sub-segment, otherwise return None. get_topological_section() Returns the topological section that the shared sub-segment was obtained from. get_topological_section_feature() Returns the feature referenced by the topological section. get_topological_section_geometry() Returns the topological section geometry that the shared sub-segment was obtained from.
get_feature()
get_geometry()
get_overriding_and_subducting_plates([return_subduction_polarity=False])

Returns the overriding and subducting plates at this subduction zone.

Parameters: return_subduction_polarity (bool) – whether to also return the subduction polarity a 2-tuple containing the overriding and subducting resolved boundaries/networks, or a 3-tuple that also contains the subduction polarity (eg, ‘Left’, ‘Right’, ‘Unknown’) if return_subduction_polarity is True, or None if the subduction polarity is not properly set or there are not exactly 2 topologies sharing this sub-segment 2-tuple of ReconstructionGeometry, or 3-tuple adding a str, or None

Note

Returns None if either the subduction polarity is not properly set or there are not exactly 2 topologies sharing the sub-segment.

To find the overriding and subducting plate IDs of all subduction zone lines:

# Resolve our topological plate polygons (and deforming networks) to the current 'time'.
# We generate both the resolved topology boundaries and the boundary sections between them.
resolved_topologies = []
shared_boundary_sections = []
pygplates.resolve_topologies(topology_features, rotation_model, resolved_topologies, time, shared_boundary_sections)

# Iterate over the shared boundary sections of all resolved topologies.
for shared_boundary_section in shared_boundary_sections:

# Skip sections that are not subduction zones.
if shared_boundary_section.get_feature().get_feature_type() != pygplates.FeatureType.gpml_subduction_zone:
continue

# Iterate over the shared sub-segments of the current subducting line.
# These are the parts of the subducting line that actually contribute to topological boundaries.
for shared_sub_segment in shared_boundary_section.get_shared_sub_segments():

# Get the overriding and subducting resolved plates/networks on either side of the current shared sub-segment.
overriding_and_subducting_plates = shared_sub_segment.get_overriding_and_subducting_plates(True)
if overriding_and_subducting_plates:
overriding_plate, subducting_plate, subduction_polarity = overriding_and_subducting_plates
overriding_plate_id = overriding_plate.get_feature().get_reconstruction_plate_id()
subducting_plate_id = subducting_plate.get_feature().get_reconstruction_plate_id()


New in version 23.

get_resolved_feature()

Returns a feature containing the resolved sub-segment geometry.

Return type: Feature

The returned feature contains the resolved geometry.

Note

The returned feature does not contain present-day geometry as is typical of most GPlates features.
In this way the returned feature is similar to a GPlates reconstruction export.

Note

The returned feature should not be reverse reconstructed to present day because the topological section might be a ResolvedTopologicalLine which is a topology and topologies are resolved (not reconstructed).

get_resolved_geometry()

Returns the geometry containing the shared sub-segment vertices.

Return type: PolylineOnSphere

Note

These are the unreversed vertices. They are in the same order as the geometry of get_topological_section_geometry(). If you need a reversed version of this resolved geometry (eg, due to get_sharing_resolved_topology_geometry_reversal_flags() returning True for a particular topology) then you can use pygplates.PolylineOnSphere(sub_segment.get_resolved_geometry()[::-1]).

get_sharing_resolved_topologies()

Returns a list of resolved topologies sharing this sub-segment.

Return type: list of ReconstructionGeometry

Note

The resolved topologies (that share this sub-segment) can be ResolvedTopologicalBoundary and ResolvedTopologicalNetwork.
ResolvedTopologicalLine is excluded since it does not have a boundary.
get_sharing_resolved_topology_geometry_reversal_flags()

Returns a list of flags indicating whether a copy of the sub-segment geometry was reversed when contributing to each resolved topology sharing this sub-segment.

Return type: list of bool

Note

The returned list is in the same order (and has the same number of elements) as the list of sharing resolved topologies returned in get_sharing_resolved_topologies().

sharing_resolved_topologies = shared_sub_segment.get_sharing_resolved_topologies()
geometry_reversal_flags = shared_sub_segment.get_sharing_resolved_topology_geometry_reversal_flags()
for index in range(len(sharing_resolved_topologies)):
sharing_resolved_topology = sharing_resolved_topologies[index]
geometry_reversal_flag = geometry_reversal_flags[index]

get_sub_segments()

If this sub-segment is from a topological line section then return the child sub-segments of the topological line contributing to this sub-segment, otherwise return None.

Return type: list of ResolvedTopologicalSubSegment, or None

To see if a shared sub-segment is from a topological line and then iterate over its child sub-segments:

child_sub_segments_of_topological_line_shared_sub_segment = shared_sub_segment.get_sub_segments()
if child_sub_segments_of_topological_line_shared_sub_segment:
for child_sub_segment in child_sub_segments_of_topological_line_shared_sub_segment:
child_sub_segment_geometry = child_sub_segment.get_resolved_geometry()
child_sub_segment_plate_id = child_sub_segment.get_feature().get_reconstruction_plate_id()
else:
sub_segment_geometry = shared_sub_segment.get_resolved_geometry()
sub_segment_plate_id = shared_sub_segment.get_feature().get_reconstruction_plate_id()


Note

Each child sub-segment has its own reverse flag indicating whether it was reversed when contributing to this shared sub-segment. And this shared sub-segment also has a reverse flag, for each final boundary topology that shares it, which determines whether this shared sub-segment was reversed when contributing to each final boundary topology. So whether a child sub-segment was effectively reversed when contributing to a final boundary topology depends on both reverse flags (of the child sub-segment and this shared sub-segment). For example, if the child sub-segment was reversed in this shared sub-segment, and this shared sub-segment was reversed in a final boundary, then the child sub-segment was not reversed in that final boundary.

New in version 22.

get_topological_section()

Returns the topological section that the shared sub-segment was obtained from.

Return type: ReconstructionGeometry

Note

This represents the entire geometry of the topological section, not just the part that contributes to the shared sub-segment.

Note

The resolved topologies that share the topological section can be ResolvedTopologicalBoundary and ResolvedTopologicalNetwork.
get_topological_section_feature()

Returns the feature referenced by the topological section.

Return type: Feature

Note

The geometry in the returned feature represents the entire geometry of the topological section, not just the part that contributes to the shared sub-segment.

get_topological_section_geometry()

Returns the topological section geometry that the shared sub-segment was obtained from.

Return type: PolylineOnSphere

Note

This is the entire geometry of the topological section, not just the part that contributes to the shared sub-segment.