@Test
public void sub(){

    double result = 0D;
    double v1 = 456456456.46554;
    double v2 = 4545889963333333.6456;
    BigDecimal b1 = new BigDecimal(Double.toString(v1));
    BigDecimal b2 = new BigDecimal(Double.toString(v2));
    result = b1.subtract(b2).doubleValue();
    Log.d("======", "得到结果result---------->" + result);
}