software for 3-manifold topology and normal surfaces

 Regina is a suite of mathematical software for 3-manifold topologists.
 It focuses on the study of 3-manifold triangulations and normal surfaces.
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 Other highlights of Regina include angle structures, census enumeration,
 combinatorial recognition of triangulations, and high-level tasks such
 as 3-sphere recognition and connected sum decomposition. Regina comes
 with a full graphical user interface, and also offers Python bindings
 and a low-level C++ programming interface.
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 This package includes the graphical user interface and the command-line
 Python interface. The users' handbook and the API documentation are in
 the separate package regina-normal-doc, and the MPI-enabled utilities for
 high-performance clusters are in the separate package regina-normal-mpi.