demo04下右键Demo03Math
package cn.itcast.day08.demo04;
public class Demo03Math{
public static void main(String[] args){
//获取绝对值
System.out.println(Math.abs(3.14));//3.14
System.out.println(Math.abs(0));//0
System.out.println(Math.abs(-2.5));//2.5
System.out.println("==================");
//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("==================");
//向下取整，抹零
System.out.println(Math.floor(30.1));//30.0
System.out.println(Math.floor(30.9));//30.0
System.out.print(Math.floor(31.0));//31.0
System.out.println("==================");
System.out.println(Math.round(20.4));//20
System.out.println(Math.round(10.5));//11
}
}
