meataxe/mkinc(1)

1mkinc(1)                         User Commands                        mkinc(1)
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NAME

6       mkinc - compute mountains and incidence matrix of a module
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SYNOPSIS

9       mkinc [OPTIONS] <Name>
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DESCRIPTION

12       This program runs in two steps.  During the first step, all cyclic sub‐
13       modules found by mkcycl(1) are uncondensed, giving  the  local  submod‐
14       ules,  the  "mountains", of the original module.  Then, each local sub‐
15       module is projected back to the condensed module, and all  cyclic  vec‐
16       tors  which  are  contained in the image are found.  At the end of this
17       step, there is a list of local submodules and, for each  local  submod‐
18       ule, a list of cyclic subspaces in the condensed module.  This informa‐
19       tion is written to Name.mnt.
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21       In the second step, mkinc computes the incidence relation between local
22       submodules.   The  result is a matrix which contains a 1 for each inci‐
23       dence.  This matrix is written to the file Name.inc.
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OPTIONS

26       -Q     Quiet, no messages.
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28       -V     Verbose, more messages.
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30       -T <MaxTime>
31              Set CPU time limit
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33       -G     Produce output in GAP format.  This option implies -Q.
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IMPLEMENTATION DETAILS

36       The whole calculation of step 2 is done in the condensed modules.  This
37       is  possible  because incidences between local submodules do not change
38       if they are condensed.  Usually this saves a lot of both memory and CPU
39       time  because  one  does not have to keep all mountains simultaneously,
40       and the condensed modules have a smaller dimension.
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INPUT FILES

43       Name.cfinfo
44              Constituent info file.
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46       Name<Cf>.{1,2,...}
47              Generators on the constituents.
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49       Name<Cf>.{1,2,...}k
50              Generators on the condensed modules.
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52       Name<Cf>.v
53              Cyclic submodules, generated by mkcycl(1).
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55       Name<Cf>.im
56              Images used for condensation.
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58       Name<Cf>.k
59              Uncondense matrices.
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OUTPUT FILES

62       Name.cfinfo
63              Constituent info file.
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65       Name.v Mountains.
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67       Name.mnt
68              Mountain dimensions and classes of cyclic submodules correspond‐
69              ing to the mountains.
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71       Name.inc
72              Incidence matrix.
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