BigDecimal b1 = new BigDecimal(Double.toString(v1));
BigDecimal b2 = new BigDecimal(Double.toString(v2));
rslt = b1.divide(b2, scale, BigDecimal.ROUND_HALF_UP).doubleValue();// scale表示表示需要精确到小数点以后几位;BigDecimal.ROUND_HALF_UP 表明四舍五入
BigDecimal b1 = new BigDecimal(Double.toString(v1));
BigDecimal b2 = new BigDecimal(Double.toString(v2));
rslt = b1.divide(b2, scale, BigDecimal.ROUND_HALF_UP).doubleValue();// scale表示表示需要精确到小数点以后几位;BigDecimal.ROUND_HALF_UP 表明四舍五入