PyNormaliz - An interface to Normaliz
What is PyNormaliz
PyNormaliz provides an interface to Normaliz (https://www.normaliz.uni-osnabrueck.de) via libNormaliz. It offers the complete functionality of Normaliz, and can be used interactively from python. For a first example, see this introduction by Richard Sieg.
Requirements
- python 2.7 or higher or python 3.4 or higher
- Normaliz 3.2.1 or higher (https://github.com/Normaliz/Normaliz/releases)
The source packages of the Normaliz realeases contains PyNormaliz.
Installation
The PyNormaliz install script assumes that you have executed the
install_normaliz_with_qnormaliz_eantic.sh
script. To install PyNormaliz and navigate to the Normaliz directory and type
python setup.py install --user
The script can be customized by some options. See Appendix E of the Normaliz manual.
Usage
The main command is Cone to create a cone, and the member functions of the cone class to compute properties. For a full list of input and output properties, see the Normaliz manual.
To create a cone, use
import PyNormaliz
C = PyNormaliz.Cone(cone = [[1,0],[0,1]])
All possible Normaliz input types can be given as keyword arguments.
To compute a property of the cone, use the provided getters, which correspond to Normaliz computation goals.
C.HilbertBasis()
You can pass options to the compute functions
C.HilbertSeries(HSOP = True)
Low level commands
There is also a low-level API, directly using C functions:
To create a cone, use
C = NmzCone("cone", [[1,0],[0,1]])
or, equivalently,
C = NmzCone(["cone", [[1,0],[0,1]]])
NmzCone can take an arbitrary number of arguments, either as separated arguments or in a list. First is always a string, describing an input property for Normaliz, followed by a (possibly empty) matrix.
NmzCompute takes a cone as first argument, followed by arbitrary many strings, or a list of strings, describing Normaliz output types. NmzCompute lets Normaliz compute the necessary values, and returns true if everything was computed properly, false otherwise.
NmzCompute(C, "HilbertBasis")
or
NmzCompute(C, ["HilbertBasis"])
NmzIsComputed takes a cone and a string representing an output property, and returns true if the property is already computed for the cone, false otherwise. (In contrast to NmzCompute it does not start a computation.)
NmzIsComputed(C, "HilbertBasis")
NmzResult takes a cone and a string representing an output property, and returns the computed value of this property as a matrix, a list, or as a bool.
NmzResult(C, "HilbertBasis")