Generate cdd .ext / .ine file format - Combinatorial and Discrete Geometry

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# 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