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Program Is_finite


Is_finite 'file1' [-M] [-N] [-o]
file1: bravais_TYP.


Decides whether the given INTEGRAL matrix group is finite. If it is so, it will echo the order of the group.


 -M   : Output generators for the Minkowski kernel (i.e the
        subgroup of all matrices congruent I mod 2) of
        the group. WARNING: these generators will be
        correct iff the group was finite. Otherwise
        the program terminates immediatly if it has calculated
        enough element of the kernel to prove the group to
        be infinite.
 -N   : Assume the group to be generated by G->gen, G->normal
        and G->cen.
 -o   : just output the order in a way that can be appended to
        a bravais_TYP.


See also for Order.


  1. How do the Z-classes in the Q-class of a given group distribute into their Bravais flocks?
  2. Do given matrices generate a space group? If so, find its name and normal representation.
  3. Is the normalizer of a given group finite?
  4. Do two given groups have Z-equivalent copies which lie in a finite unimodular group?

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