Description: |
GAP package CRISP: Computing with Radicals, Injectors, Schunck classes and Projectors. The GAP package CRISP provides algorithms for computing subgroups of finite soluble groups related to a group class C. In particular, it allows to compute C-radicals and C-injectors for Fitting classes (and Fitting sets) C, C-residuals for formations C, and C-projectors for Schunck classes C. In order to carry out these computations, the group class C must be represented by an algorithm which can decide membership in the group class. Moreover, CRISP contains algorithms for the computation of normal subgroups invariant under a prescribed set of automorphisms and belonging to a given group class. This includes an improved method to compute the set of all normal subgroups of a finite soluble group, its characteristic subgroups, minimal normal subgroups and the socle and p-socles for given primes p. |