action.c

/****************************************************************************
**
*A  action.c                    ANUPQ source                   Eamonn O'Brien
**
*Y  Copyright 1995-2001,  Lehrstuhl D fuer Mathematik,  RWTH Aachen,  Germany
*Y  Copyright 1995-2001,  School of Mathematical Sciences, ANU,     Australia
**
*/

#include "pq_defs.h"
#include "constants.h"
#include "pcp_vars.h"
#include "pq_functions.h"
#include "standard.h"
#include "word_types.h"

/* specify automorphims in terms of defining generators
   and compute resultant action on pc generators;
   return action as array auts */

int ***determine_action(int format, int *nmr_of_auts, struct pcp_vars *pcp)
{
   register int *y = y_address;

   register int i, j, k;
   int ***auts;
   int cp, pcp_generator;

   read_value(TRUE, "Input the number of automorphisms: ", nmr_of_auts, 0);

   auts = allocate_array(*nmr_of_auts, pcp->lastg, pcp->lastg, TRUE);

   cp = pcp->lused;
   for (i = 1; i <= *nmr_of_auts; ++i) {
      printf("Now enter the data for automorphism %d\n", i);
      for (j = 1; j <= pcp->ndgen; ++j) {
         pcp_generator = y[pcp->dgen + j];
         printf("Input image of defining generator %d as word:\n", j);
         setup_defgen_word_to_collect(stdin, format, ACTION, cp, pcp);
         if (pcp_generator > 0) {
            for (k = 1; k <= pcp->lastg; ++k)
               auts[i][pcp_generator][k] = y[cp + k];
         }
      }
   }

   extend_automorphisms(auts, *nmr_of_auts, pcp);
   print_auts(*nmr_of_auts, pcp->lastg, auts, pcp);

   return auts;
}