Generate cdd .ext / .ine file format

sage.geometry.polyhedron.cdd_file_format.cdd_Hrepresentation(cdd_type, ieqs, eqns, file_output=None)

Return a string containing the H-representation in cddlib’s ine format.

INPUT:

• file_output – string (optional); a filename to which the representation should be written. If set to None (default), representation is returned as a string.

EXAMPLES:

Sage

sage: from sage.geometry.polyhedron.cdd_file_format import cdd_Hrepresentation
sage: cdd_Hrepresentation('rational', None, [[0,1]])
'H-representation\nlinearity 1 1\nbegin\n 1 2 rational\n 0 1\nend\n'

Python

>>> from sage.all import *
>>> from sage.geometry.polyhedron.cdd_file_format import cdd_Hrepresentation
>>> cdd_Hrepresentation('rational', None, [[Integer(0),Integer(1)]])
'H-representation\nlinearity 1 1\nbegin\n 1 2 rational\n 0 1\nend\n'

sage.geometry.polyhedron.cdd_file_format.cdd_Vrepresentation(cdd_type, vertices, rays, lines, file_output=None)

Return a string containing the V-representation in cddlib’s ext format.

INPUT:

• file_output – string (optional); a filename to which the representation should be written. If set to None (default), representation is returned as a string.

Note

If there is no vertex given, then the origin will be implicitly added. You cannot write the empty V-representation (which cdd would refuse to process).

EXAMPLES:

Sage

sage: from sage.geometry.polyhedron.cdd_file_format import cdd_Vrepresentation
sage: print(cdd_Vrepresentation('rational', [[0,0]], [[1,0]], [[0,1]]))
V-representation
linearity 1 1
begin
  3 3 rational
  0 0 1
  0 1 0
  1 0 0
end

Python

>>> from sage.all import *
>>> from sage.geometry.polyhedron.cdd_file_format import cdd_Vrepresentation
>>> print(cdd_Vrepresentation('rational', [[Integer(0),Integer(0)]], [[Integer(1),Integer(0)]], [[Integer(0),Integer(1)]]))
V-representation
linearity 1 1
begin
  3 3 rational
  0 0 1
  0 1 0
  1 0 0
end