Java （六）：java中Math常用方法

package com.niuke.test;


public class MathD {

    public static void main(String[] args) {
        
        
        /**  
         * abs求绝对值  
         */    
        System.out.println(Math.abs(-10.4));    //10.4    
        System.out.println(Math.abs(10.1));     //10.1    
        /**  
         * ceil天花板的意思，就是返回大的值，注意一些特殊值  
         */    
        System.out.println(Math.ceil(-10.1));   //-10.0    
        System.out.println(Math.ceil(10.7));    //11.0    
        System.out.println(Math.ceil(-0.7));    //-0.0    
        System.out.println(Math.ceil(0.0));     //0.0    
        System.out.println(Math.ceil(-0.0));    //-0.0 
        System.out.println("my name is -0.5 "+Math.ceil(-0.5));
    
        /**  
         * floor地板的意思，就是返回小的值  
         */    
        System.out.println(Math.floor(-10.1));  //-11.0    
        System.out.println(Math.floor(10.7));   //10.0    
        System.out.println(Math.floor(-0.7));   //-1.0    
        System.out.println(Math.floor(0.0));    //0.0    
        System.out.println(Math.floor(-0.0));   //-0.0    
            
        /**  
         * max 两个中返回大的值,min和它相反，就不举例了  
         */    
        System.out.println(Math.max(-10.1, -10));   //-10.0    
        System.out.println(Math.max(10.7, 10));     //10.7    
        System.out.println(Math.max(0.0, -0.0));    //0.0    
            
        /**  
         * random 取得一个大于或者等于0.0小于不等于1.0的随机数  
         */    
        System.out.println(Math.random());  //0.08417657924317234    
        System.out.println(Math.random());  //0.43527904004403717    
            
        /**  
         * rint 四舍五入，返回double值  
         * 注意.5的时候会取偶数  
         */    
        System.out.println(Math.rint(10.1));    //10.0    
        System.out.println(Math.rint(10.7));    //11.0    
        System.out.println(Math.rint(11.5));    //12.0    
        System.out.println(Math.rint(10.5));    //10.0    
        System.out.println(Math.rint(10.51));   //11.0    
        System.out.println(Math.rint(-10.5));   //-10.0    
        System.out.println(Math.rint(-11.5));   //-12.0    
        System.out.println(Math.rint(-10.51));  //-11.0    
        System.out.println(Math.rint(-10.6));   //-11.0    
        System.out.println(Math.rint(-10.2));   //-10.0    
            
        /**  
         * round 四舍五入，float时返回int值，double时返回long值  
         */    
        System.out.println(Math.round(10.1));   //10    
        System.out.println(Math.round(10.7));   //11    
        System.out.println(Math.round(10.5));   //11    
        System.out.println(Math.round(10.51));  //11    
        System.out.println(Math.round(-10.5));  //-10    
        System.out.println(Math.round(-10.51)); //-11    
        System.out.println(Math.round(-10.6));  //-11    
        System.out.println(Math.round(-10.2));  //-10    
    
    
    
    }
}