Function to normalize any number from 0 - 1
Using Nathan Bertons's answer with a preconfigured function for some values with the same min and max values, you could use this.
function normalize(min, max) {
var delta = max - min;
return function (val) {
return (val - min) / delta;
};
}
console.log([5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15].map(normalize(5, 15)));I prefer using this formula when I want to normalize a value between two ranges with known min, max values. You can add checks to constrain the input, although this will correctly calculate the difference from the new range if an out-of-range value is given as input.
/**
* Normalizes a value from one range (current) to another (new).
*
* @param { Number } val //the current value (part of the current range).
* @param { Number } minVal //the min value of the current value range.
* @param { Number } maxVal //the max value of the current value range.
* @param { Number } newMin //the min value of the new value range.
* @param { Number } newMax //the max value of the new value range.
*
* @returns { Number } the normalized value.
*/
const normalizeBetweenTwoRanges = (val, minVal, maxVal, newMin, newMax) => {
return newMin + (val - minVal) * (newMax - newMin) / (maxVal - minVal);
};
const e = document.getElementById('result');
e.innerHTML = normalizeBetweenTwoRanges(10, 5, 15, 0, 1);<span id="result"></span>Why not just:
function(val, max, min) { return (val - min) / (max - min); }