java基础 Math

 

package cn.mantishell.day08.demo04;

/**
 * java.util.Math类是数学相关的工具类，里面提供类大量的静态方法，完成与数学运算相关的操作
 *
 * public static double abs(double num);获取绝对值
 * public static double ceil(double num);向上取整
 * public static double floor(double num);向下取整
 * public static long round(double num);四舍五入
 */
public class Demo03Math {
    public static void main(String[] args) {
        //获取绝对值
        System.out.println(Math.abs(-2.5));//2.5
        //向上取整
        System.out.println(Math.ceil(3.9));//4.0
        System.out.println(Math.ceil(3.1));//4.0
        System.out.println(Math.ceil(3.0));//3.0

        System.out.println(Math.floor(10.9));

        System.out.println(Math.round(2.6));
    }
}