An improved algorithm for quadratic equation classification and Petrov classification
The Petrov class is determined by the five (complex) Weyl tensor components. 32 different cases can be distinguished depending on whether one or several of these components are zero or not. The proposed algorithm differs from its predecessors mainly in that for each of these 32 cases a (slightly) different procedure is used, such avoiding the discussion of subcases which otherwise arise.
scientific article; zbMATH DE number 4046616