code: func (r *Row) IsEmpty() bool {
  	if len(r.segments) == 0 {
  		return true
  	}
  	for i := range r.segments {
  		if r.segments[i].n > 0 {
  			return false
  		}
  
  	}
  	return true
  }
docs: // IsEmpty returns true if the row doesn't contain any set bits.