public Double getColTotal(int position) {
        Double total = 0d;
        
        if (position < Cols()) {
            DMemeList tmp = copyColumn(position);
            if (tmp.size() > 0) {
                for (DataMeme dm : tmp) {
                    Double i = dm.asDouble();
                    if (i != null) { total += i; }
                }
            }
        }
                
        return total;
    }