java Math类方法使用

package math;

public class MathMethod {
    public static void main(String[] args) { System.out.println(Math.abs(10));//10
    System.out.println( Math.abs(-10));//10
    //pow
    System.out.println((int) Math.pow(2,4));//16
    System.out.println(Math.pow(2,-4));

    System.out.println(Math.ceil(1.001));
    System.out.println(Math.floor(-1.001));

    System.out.println(Math.round(1.54));

    System.out.println(Math.sqrt(9.0));

    System.out.println(Math.random());
    int a=2;
    int b=7;
    int num=a+(int)(Math.random()*(b-a+1));
    System.out.println("num="+ num);

    System.out.println(Math.max(1.0,7.8));
    System.out.println(Math.min(12l,78l));

    }
}

结果：

10
10
16
0.0625
2.0
-2.0
2
3.0
0.2695117759347122
num=7
7.8
12