pygplates.ReconstructionTreeEdge

class pygplates.ReconstructionTreeEdge

Bases: Boost.Python.instance

A reconstruction tree edge represents a moving/fixed plate pair in the graph of the plate-reconstruction hierarchy. See Plate reconstruction hierarchy.

__init__()

Raises an exception This class cannot be instantiated from Python

Methods

__init__	Raises an exception This class cannot be instantiated from Python
get_child_edges()	Returns a view, of the child edges of this edge, that supports iteration over the child edges as well as indexing into the child edges.
get_equivalent_total_rotation()	Return equivalent (relative to the anchor plate) finite rotation of the moving plate of this edge.
get_fixed_plate_id()	Return the fixed plate id of this edge.
get_moving_plate_id()	Return the moving plate id of this edge.
get_parent_edge()	Return the parent edge of this edge, or None if this edge has no parent.
get_relative_total_rotation()	Return finite rotation of the moving plate of this edge relative to the fixed plated id of this edge.

get_child_edges()

Returns a view, of the child edges of this edge, that supports iteration over the child edges as well as indexing into the child edges.

A child edge is one step further from the top (or root) of the reconstruction tree (further from the anchor plate). The fixed plate id of each child edge matches the moving plate id of this edge.

Note that the view object returned by this method is not a list or an iterator but, like dictionary views in Python 3, a list or iterator can be obtained from the view as in list(edge.get_child_edges()) or iter(edge.get_child_edges()).

The returned view provides the following operations for accessing the child edges:

Operation	Result
len(child_edges)	number of child edges
for e in child_edges	iterates over the child edges e
child_edges[i]	the child edge at index i

The following example demonstrates top-down (starting at the anchored plate) traversal of the reconstruction tree:

def traverse_sub_tree(edge):
    print 'Parent plate: %d, child plate:%d' % (edge.get_fixed_plate_id(), edge.get_moving_plate_id())
    # Recurse into the children sub-trees.
    for child_edge in edge.get_child_edges():
        traverse_sub_tree(child_edge)

for anchor_plate_edge in reconstruction_tree.get_anchor_plate_edges():
    traverse_sub_tree(anchor_plate_edge)

get_equivalent_total_rotation()

Return equivalent (relative to the anchor plate) finite rotation of the moving plate of this edge.

Return type

FiniteRotation

The total in the method name indicates that the rotation is also relative to present day.

This method returns the precomputed equivalent of the following (see FiniteRotation for the maths):

def get_equivalent_total_rotation(edge):
    finite_rotation = pygplates.FiniteRotation.create_identity_rotation()
    while edge:
        finite_rotation = edge.get_relative_total_rotation() * finite_rotation
        edge = edge.get_parent_edge()
    return finite_rotation

get_fixed_plate_id()

Return the fixed plate id of this edge.

Return type

int

get_moving_plate_id()

Return the moving plate id of this edge.

Return type

int

get_parent_edge()

Return the parent edge of this edge, or None if this edge has no parent.

This method can be used to traverse the plate circuit from an arbitrary plate (moving plate id on an edge) to the anchor plate (terminating at None) and visiting moving/fixed relative plate rotations along the way.

Return type

ReconstructionTreeEdge or None

The parent edge is one step closer to the top (or root) of the reconstruction tree (closer to the anchor plate). The moving plate id of the parent edge matches the fixed plate id of this edge.

None is returned if this edge is already at the top of the reconstruction tree (if its fixed plate id is the anchor plate id).

The following example demonstrates following the plate circuit path from a plate (moving plate of an edge) to the anchor plate (at the top/root of the reconstruction tree):

while True:
    print 'Plate: %d' % edge.get_moving_plate_id()
    if not edge.get_parent_edge():
        print 'Anchored plate: %d' % edge.get_fixed_plate_id()
        break
    edge = edge.get_parent_edge()

get_relative_total_rotation()

Return finite rotation of the moving plate of this edge relative to the fixed plated id of this edge.

Return type

FiniteRotation

The total in the method name indicates that the rotation is also relative to present day.