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example$ regina-python
Regina 7.0
Software for low-dimensional topology
Copyright (c) 1999-2021, The Regina development team
>>> ################################
>>> #
>>> # Sample Python Script
>>> #
>>> # Illustrates the traversal and manipulation of an entire packet tree.
>>> #
>>> # See the file "tree.session" for the results of running this script.
>>> #
>>> ################################
>>>
>>> # Recreate the original SnapPea census of cusped hyperbolic manifolds
>>> # triangulated by at most 5 tetrahedra.
>>> #
>>> # Since we are building a packet tree, we need to use PacketOfTriangulation3,
>>> # not the plain type Triangulation3 (which is not a packet type).
>>> census = Container()
>>> for i in range(415):
... mfd = SnapPeaCensusManifold(SnapPeaCensusManifold.SEC_5, i)
... census.append(make_packet(mfd.construct(), mfd.name()))
...
>>> # The triangulations are now all children of the "census" container.
>>> # Remove all triangulations with more than two tetrahedra.
>>> #
>>> # Since we are deleting children, we step through the children manually
>>> # instead of just iterating over children().
>>> tri = census.firstChild()
>>> while tri != None:
... next = tri.nextSibling()
... if tri.size() > 2:
... tri.makeOrphan()
... tri = next
...
>>> # Print the homology of each remaining triangulation.
>>> # This time we are not adding or removing children, so we can just iterate.
>>> for tri in census.children():
... print(tri.label() + ":", tri.homology())
...
Gieseking manifold: Z
SnapPea m001: Z + Z_2
SnapPea m002: Z + Z_2
SnapPea m003: Z + Z_5
Figure eight knot complement: Z
>>>
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