JAVA Math類

Math.sqrt()//     

Math.cbrt()//     

Math.pow(a, b)//  a b  

Math.max( , );//     

Math.min( , );//     

Math.abs    

Math.ceil      ，        

Math.floor     ，       

Math.random           0.0     1.0    

Math.rint     ，  double 

public class MathTest{
      public static void main(String args[]){ 
        /** 
         *Math.sqrt()//     
         *Math.cbrt()//     
         *Math.pow(a, b)//  a b  
         *Math.max( , );//     
         *Math.min( , );//     
         */
        System.out.println(Math.sqrt(16));  //4.0 
        System.out.println(Math.cbrt(8));  //2.0
        System.out.println(Math.pow(3,2));   //9.0
        System.out.println(Math.max(2.3,4.5));//4.5
        System.out.println(Math.min(2.3,4.5));//2.3
        /** 
         * abs     
         */
        System.out.println(Math.abs(-10.4));  //10.4 
        System.out.println(Math.abs(10.1));   //10.1 
        /** 
         * ceil      ，       
         */
        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(Math.ceil(-1.7));  //-1.0
        /** 
         * floor     ，        
         */
        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 
        /** 
         * random           0.0     1.0     
         */
        System.out.println(Math.random()); //  1  0 double    
        System.out.println(Math.random()*2);//  0  1 double    
        System.out.println(Math.random()*2+1);//  1  2 double    
        /** 
         * rint     ，  double  
         *   .5         
         */
        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     ，float   int ，double   long  
         */
        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 
      } 
    }