Usage and related functions for generating random numbers in JS, and usage functions for js random numbers

First, we will introduce some functions related to random numbers:

Var Rand = Math. random ();

- 1. Math. random (); the result is a random number (including 0, not 1) between 0 and 1)
- 2. Math. floor (num); The num parameter is a numerical value, and the function result is an integer part of num.
- 3. Math. round (num); The num parameter is a numerical value, and the function result is an integer rounded to num.

**Math:**Mathematical object that provides mathematical calculation of data.

**Math. random ();**Returns a random number between 0 and 1 (including 0, excluding 1.

**Math. ceil (n );**Returns the smallest integer greater than or equal to n.

Use**Math. ceil (Math. random () * 10 );**Obtain a random integer ranging from 1 to 10. The probability of getting 0 is very small.

**Math. round (n );**Returns the integer value after n rounding.

Use**Math. round (Math. random ());**Returns a random integer ranging from 0 to 1.

Use**Math. round (Math. random () * 10 );**You can obtain a random integer ranging from 0 to 10 in a balanced manner. The probability of obtaining a minimum value of 0 and a maximum value of 10 is less than half.

**Math. floor (n );**Returns the largest integer less than or equal to n.

Use**Math. floor (Math. random () * 10 );**You can obtain random integers ranging from 0 to 9 in a balanced manner.

The random lottery can also be expanded. For example, you can set the probability of a lottery and use it with the database.

// Demand for the probability of winning, 100% winning, three prizes, but the probability of getting a book is 20% function draw () {var d_s = GetRandom (100 ); if (d_s> = 1 & d_s <= 40) {alert ('Congratulations, you have drawn XXX! ');} Else if (d_s> = 41 & d_s <= 80) {alert ('Congratulations, you have drawn XXX! ');} Else {alert (' congratulations, you have obtained the book! ');}}

Function Code for generating random numbers in the corresponding js:

<script> 2function GetRandomNum(Min,Max){ var Range = Max - Min; var Rand = Math.random(); return(Min + Math.round(Rand * Range)); } 8var num = GetRandomNum(1,10); 9alert(num); </script>var chars = ['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'];function generateMixed(n) { var res = ""; for(var i = 0; i < n ; i ++) { var id = Math.ceil(Math.random()*35); res += chars[id]; } return res;}

The above is the detailed content of this article, hoping to help you learn.

Articles you may be interested in:

- Comparison of Methods for obtaining non-repeated random numbers using javascript
- Javascript generates random numbers within a specified range
- Js gets any random array element that does not repeat.
- Js random number generates 6 digits
- In JavaScript code, the random number is added after the ajax request address to prevent browser caching.
- Random Number generated by js: random example of the random function
- JS generates 20 random numbers 0-9 as an example can also be a-z A-Z
- Use the js Math. random () function to generate random numbers between n and m.
- Javascript generates a random Random Number of up to 13 m bits based on time
- Javascript to obtain random numbers of four digits or letters