SMbounds()

void SchurRing2::SMbounds ( int & lo, int & hi )

private

Definition at line 748 of file schur2.cpp.

{
  int i, k;
  int x = SMfilled.xloc[SMcurrent];
  int y = SMfilled.yloc[SMcurrent];
 
  // First set the high bound, using info from the "one to the right"
  // in the reverse lex filled skew tableau.
 
  if (y == SMfilled.p[x])  // There is not one to the right
    {
      hi = SMmaxrows;
      for (k = 1; k <= SMmaxrows; k++)
        if (SMtab.p[k] == 0)
          {
            hi = k;
            break;
          }
    }
  else  // note that the case SMcurrent==1 will be handled
    {   // in the previous statement.
      hi = SMtab.xloc[SMcurrent - 1];
    }
 
  // Now we set the lo bound, using info from the "one above"
 
  if (x == 1 || y <= SMfilled.lambda[x - 1])
    lo = 1;  // There is not one above
  else
    {
      int above = SMcurrent - SMfilled.p[x] + SMfilled.lambda[x - 1];
      int xabove = SMtab.xloc[above];
      int yabove = SMtab.yloc[above];
      for (i = xabove + 1; i <= hi; i++)
        if (SMtab.p[i] < yabove) break;
      lo = i;
    }
}

References SMcurrent, SMfilled, SMmaxrows, SMtab, and x.

Referenced by SM().