Create value between two numbers by percentage

December 8, 2022

I have 2 arrays: [-26, -5] [-5.3, 2.3], and a percentage value from 0 to 100 that changes on scroll.

I need a function that generates a number by percentage between two numbers, where percentage 0 is the first value from the array, and where 100 percent is the second value. 50% is exactly in the middle of the two numbers. After receiving a number, reduce it to hundredths.

For example:

const result1 = someMagick(50%, [-26, -5]);
const result2 = someMagick(100%, [-26, -5]);

console.log(result1, result2)
// -16, -26

I don’t have any thoughts how to do it, please help

>Solution :

function someMagick(percentage, numbers) {
  // Convert percentage value to decimal
  const decimalPercentage = percentage / 100;

  // Calculate range between numbers
  const range = numbers[1] - numbers[0];

  // Calculate result by adding first number in array to the product of the percentage value and the range
  const result = numbers[0] + (decimalPercentage * range);

  // Return result rounded to the nearest hundredth
  return Math.round(result * 100) / 100;
}

// Example usage
const result1 = someMagick(50, [-26, -5]);
const result2 = someMagick(100, [-26, -5]);

console.log(result1, result2);
// -16, -26

You can then use this function to generate a number by percentage between two numbers in your code.