The math class contains methods for performing basic mathematical operations, such as absolute values, logarithms, square roots, and trigonometric functions. It is a final class, which defines a number of constants and static

State method. Common methods are as follows:

public static double sqrt (double A)//square root

public static double Ceil (double A)//the first integer greater than a

public static double floor (double A)//the first integer that is smaller than a

public static Double pow (double a,double b)//index, base a, b exponent

Puiblic Static Long round (double A)//rounded

public Staic int round (float a)//rounding

public static double random ()//Generate 0~1

Java three ways to generate random numbers:

1. Use System.currenttimemillis () to get a long number with a current time-millisecond number

2. Returns a random double value of 0 to 1 via math.random ()

3. Generate a random number through the random class, which is a professional random tool class, powerful

The random algorithm implemented in the random class is pseudo-random, that is, random with rules. There is an Origin seed number (seed), the same seed as the random object, generated the same number of times

The same as the random number

Construction Method:

1.public Random ()

2.public Random (Long Seed)

Common methods

public void nextbytes (byte[] bytes)

public int Nextint ()

public int Nextint (5)//[0,5) is an integer that never takes 5

public int Nextboolean ()//Boolean

public int nextfloat ()//0-1 floating point number

public int nextdouble ()//0-1 double type floating-point number

The math class contains methods for performing basic mathematical operations, such as absolute values, logarithms, square roots, and trigonometric functions. It is a final class, which defines a number of constants and static

State method. Common methods are as follows:

public static double sqrt (double A)//square root

public static double Ceil (double A)//the first integer greater than a

public static double floor (double A)//the first integer that is smaller than a

public static Double pow (double a,double b)//index, base a, b exponent

Puiblic Static Long round (double A)//rounded

public Staic int round (float a)//rounding

public static double random ()//Generate 0~1

Java three ways to generate random numbers:

1. Use System.currenttimemillis () to get a long number with a current time-millisecond number

2. Returns a random double value of 0 to 1 via math.random ()

3. Generate a random number through the random class, which is a professional random tool class, powerful

The random algorithm implemented in the random class is pseudo-random, that is, random with rules. There is an Origin seed number (seed), the same seed as the random object, generated the same number of times

The same as the random number

Construction Method:

1.public Random ()

2.public Random (Long Seed)

Common methods

public void nextbytes (byte[] bytes)

public int Nextint ()

public int Nextint (5)//[0,5) is an integer that never takes 5

public int Nextboolean ()//Boolean

public int nextfloat ()//0-1 floating point number

public int nextdouble ()//0-1 double type floating-point number

ImportJava.util.Random; Public classMathrandomdemo { Public Static voidMain (string[] args) {//TODO auto-generated Method StubSystem.out.println (Math.floor (10.55));//the first integer smaller than itSystem.out.println (Math.ceil (10.55));//the first integer larger than itSystem.out.println (Math.pow (2,3));//3 times for index 2System.out.println (Math.Round (10.6));//RoundingSystem.out.println (MATH.SQRT (64));//the first integer smaller than itSystem.out.println (Math.random ()); Random random1=NewRandom (); System.out.println (Random1.nextint ()); Random Random2=NewRandom (10);//The random number does not changeSystem.out.println (Random2.nextint ()); Random Random3=NewRandom (System.currenttimemillis ());//Sets the number to the number of milliseconds of time, which is changingSystem.out.println (Random3.nextint ()); System.out.println (Random3.nextint (5));//randomly generated [0,5], less than 5System.out.println (Random3.nextboolean ()); System.out.println (Random3.nextdouble ());//Double PrecisionSystem.out.println (Random3.nextfloat ());//Single Precision }}

Java Math Math tools and random stochastic functions