What is random() in JavaScript?
In JavaScript, random() is a built-in method that is used to return a random number in the range 0 to 1 (with 0 being inclusive and 1 exclusive). The distribution of the generated random numbers is approximately uniform. It does not actually return a whole number. Instead, it returns a floating point (decimal) value.
The random() method can only be invoked through the Math object because it is a function of this object. This means that it can also be referred to as a Math function.
Math.random()
There are no parameters or arguments for this function
The random() function returns a value in the range 0 to 1, where 0 is inclusive and 1 is exclusive.
Generating numbers from 0 to 1
Let’s take an example that describes how to use the random() method in JavaScript.
console.log(Math.random())//0.3954510201227812console.log(Math.random())//0.14764999900801512
The numbers returned will be different for every method call.
Generating numbers in custom ranges
By default, random() returns a floating point value between 0 and 1. However, different ranges of random numbers can easily be generated.
Generating a random number between 0 and a specified number
In this, we want to generate random numbers between 0 and a, where a is the specified number .
Math.random() * a;
In this example, we want to generate random numbers between 0 and 15. To do this, we multiply the result of Math.random() by 15:
var result ;for (var i = 0; i < 5; i++){result = Math.random() * 15;console.log(result)}
In the code above, we used the random() function inside the for loop to generate 5 random numbers between 0 and 15.
Generating a random number within a range of values
In this, we want to generate random numbers between b and c. To do this, the difference of both numbers is multiplied by the Math.random() and the lesser number is added.
Math.random() * ( c - b) + b
var result ;var b = 100;var c = 500;for (var i = 0; i < 5; i++){result = Math.random() * (c - b) + b;console.log(result)}
In the code above, we used the random() function inside the for loop to generate 5 random numbers between 100 and 500. To achieve this, we assign both numbers to variables b and c.
Application
The random() method has various applications including gaming, text generator, number generator, generative art.
Next you will see a mini dice game that is built using the random() method.
The code for this game can be seen by clicking on other tabs.
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CONTRIBUTOR
Mary Okosun