Method dorescale

LASzip/unused/rangemodel.cpp:95–150

rescale frequency counts */

/* rescale frequency counts */
void RangeModel::dorescale()
{
  I32 i, c, missing;
  if (nextleft)  /* we have some more before actual rescaling */
  {
    incr++;
    left = nextleft;
    nextleft = 0;
    return;
  }
  if (rescale != targetrescale)  /* double rescale interval if needed */
  {
    rescale <<= 1;
    if (rescale > targetrescale)
    {
      rescale = targetrescale;
    }
  }
  c = missing = cf[n];  /* do actual rescaling */
  for(i=n-1; i; i--)
  {
    I32 tmp = newf[i];
    c -= tmp;
    cf[i] = c;
    tmp = tmp>>1 | 1;
    missing -= tmp;
    newf[i] = tmp;
  }
  if (c!=newf[0])
  {
//    fprintf(stderr,"BUG: rescaling left %d total frequency\n",c);
//    exit(1);
    throw std::runtime_error("internal error: RangeModel::dorescale()");
  }
  newf[0] = newf[0]>>1 | 1;
  missing -= newf[0];
  incr = missing / rescale;
  nextleft = missing % rescale;
  left = rescale - nextleft;
  if (search != NULL)
  {
    i=n;
    while (i)
    {
      I32 start, end;
      end = (cf[i]-1) >> searchshift;
      i--;
      start = cf[i] >> searchshift;
      while (start<=end)
      {
        search[start] = i;
        start++;
      }
    }
  }
}

/* reinitialisation of qsmodel                         */