Independent random generations in Javascript / p5.js

Question

In P5.js, I often have to write more than one line of random in order to get independent random generation such as:

 random(); random(); random(); // or a = random(); b = random(); c = random(); //etc

is there any alternative code(s) in p5.js or javascript that can perform the same/similar generations and so the code efficiency can be improve? Thanks

Answer 1

If you're putting random numbers into an array, you can do it concisely with Array.from :

 const random = () => Math.random(); const arr = Array.from({ length: 3 }, random); console.log(arr);

You can do the same sort of thing for multiple separate variables by destructuring:

 const random = () => Math.random(); const [a, b, c] = Array.from({ length: 3 }, random); console.log(a); console.log(b); console.log(c);

If you need to call random with certain parameters, then:

 const random = (low, high) => Math.floor((high - low) * Math.random()) + low; const [a, b, c] = Array.from({ length: 3 }, () => random(1, 4)); console.log(a); console.log(b); console.log(c);

Answer 2

If you would rather not perform random calculations within draw() then you could generate an array of pre-calculated random numbers in setup. When you need a random number you just grab one from the array.

let rndListLength = 100;
let rndNums;

function setup() {  
  rndNums = [...Array(rndListLength).keys()].map(a => random());

  // Show complete list
  console.log(rndNums);

  // Show number 17 in list 
  // (remember the first array index is always 0)
  console.log(rndNums[16]);
}