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JavaScript

Posted by Unsubscribed User
.a{fill-rule:evenodd;}techdegree
Unsubscribed User
Full Stack JavaScript Techdegree Student 1,198 Points

Is my formula correct to 2 random numbers between 2 values? when I output the result it seems everything is working fine

/**
 * Returns a random number between two numbers.
 *
 * @param {number} lower - The lowest number value.
 * @param {number} upper - The highest number value.
 * @return {number} The random number value.
 */
const randomNumber = (upper, lower) => Math.floor(Math.random() * (upper -lower)) + lower;

// Call the function and pass it different values
console.log(randomNumber(50,34));

2 Answers

Peter Vann
Peter Vann
36,427 Points

Hi Ismael!

This will give you a random number between (and including) two numbers:

const randNumBtwn = (min, max) => Math.floor(Math.random() * (max - min + 1)) + min;

Your version does not ever include the upper/max value.

I hope that helps.

Stay safe and happy coding!

Unsubscribed User
.a{fill-rule:evenodd;}techdegree
Unsubscribed User
Full Stack JavaScript Techdegree Student 1,198 Points

great, thanks!

Peter Vann
Peter Vann
36,427 Points
Peter Vann
Peter Vann
36,427 Points

Hi Ismael!

I thought about it some more and here is a way to generate a random number BETWEEN two numbers (excluding both those numbers). It is possible there is a cleaner way to do it, but this at least works:

const getRandomNum = (min, max) => {
  let randNum = Math.floor(Math.random() * (max - min)) + min; // max is excluded already (got rid of + 1)
  if (randNum == min) { // Exclude min
    randNum = getRandomNum(min, max) // Yes, it's using recursion!?!
  }
  return randNum;  
}

If randNum == min, it generates a different number, thus excluding min, yet still producing a random number.

I hope that helps.

Stay safe and happy coding!