java中Math类的常用API

public static int abs(int a)：绝对值

public static double ceil(double a):向上取整

public static double floor(double a):向下取整

public static int max(int a,int b):最大值

public static double pow(double a,double b):a的b次幂

public static double random():随机数 [0.0,1.0)

public static int round(float a) 四舍五入(参数为double的自学)

public static double sqrt(double a):正平方根

// 绝对值
System.out.println("abs:" + Math.abs(10));
System.out.println("abs:" + Math.abs(-10));

// 向上取整
System.out.println("ceil:" + Math.ceil(12.34));
System.out.println("ceil:" + Math.ceil(12.56));

// 向下取整
System.out.println("floor:" + Math.floor(12.34));
System.out.println("floor:" + Math.floor(12.56));

// 最大值
System.out.println("max:" + Math.max(12, 23));

//a的b次幂
System.out.println("pow:" + Math.pow(2, 3));

// 获取一个1-100之间的随机数
System.out.println("random:" + ((int) (Math.random() * 100) + 1));

// 四舍五入
System.out.println("round:" + Math.round(12.34f));
System.out.println("round:" + Math.round(12.56f));

// 正平方根
System.out.println("sqrt:"+Math.sqrt(4));