double运算的精度问题

2013-07-08 04:36:46 349 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

使用BigDecimal解决double类型数据运算的精度问题使用BigDecimal解决double类型数据运算的精度问题阅读详情



import java.math.BigDecimal;



public class TestDouble {

	public static void main(String[] args) {

		double d1 = div(20130708154752d,1000000000000d);

		double d2 = 16000d;

		System.out.println(d1);

		System.out.println(sum(d1,d2));

	}

	

	public static double sum(double d1,double d2){

		BigDecimal bd1 = new BigDecimal(Double.toString(d1));

		BigDecimal bd2 = new BigDecimal(Double.toString(d2));

		return bd1.add(bd2).doubleValue();

	}

	

	public static double div(double v1,double v2){

        return div(v1,v2,12);

    }

	

	public static double div(double v1,double v2,int scale){

        if(scale<0){

            throw new IllegalArgumentException(

                "The scale must be a positive integer or zero");

        }

        BigDecimal b1 = new BigDecimal(Double.toString(v1));

        BigDecimal b2 = new BigDecimal(Double.toString(v2));

        return b1.divide(b2,scale,BigDecimal.ROUND_HALF_UP).doubleValue();

    }

}