action_on_blocks(km, i, perm);

Assume that p normalises the group G of the KM-file. Then g permutes orbits of G for any i in 0 <= i <= k. This function computes the permutation representation of p on the orbits of size i.

Example:

fuse_orbits(km, group_fname, k);

Example:

fuse_orbits_by_representatives(rep, group_fname, k);

Example:

transversal_of_isomorphism_types(km, lambda);

This function computes a transversal of the isomorphism types of the designs for the given value of lambda which are contained in the KM-file whose name is specified in km. The transversal is given back as a vector of integers. These integers are in the range from 0 to nos -1 where nos is the number of solutions for the given value of lambda. The 0/1-solution vectors whose indices are in the returned vector form the transversal of isomorphism types of designs.

Note that this function computes a canonical labelling of all incidence matrices of designs described by the 0/1-solution vectors in the KM-file. This may take a while and is feasible only for designs whose number of points or blocks is less than a few hundred. During the processing, a database holding the transversal of designs is built. Afterwards, the indices of the designs in the transversal are given back.

There are some temporary files in the current directory created by this routine.

Example:

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Last updated: July 26, 1999, Evi Haberberger