Scaling between two number ranges

Question

I remember using an equation to do this at some point – how do you do this in Javascript?

Plugin two number ranges:

rangeX = 1 (through) 10;
rangeY =         


        

Answer 1

I turned @Foggzie's answer into a TypeScript function and ES2016 function.

TypeScript:

const scale = (inputY: number, yRange: Array, xRange: Array): number => {
  const [xMin, xMax] = xRange;
  const [yMin, yMax] = yRange;

  const percent = (inputY - yMin) / (yMax - yMin);
  const outputX = percent * (xMax - xMin) + xMin;

  return outputX;
};

ES2016:

const scale = (inputY, yRange, xRange) => {
  const [xMin, xMax] = xRange;
  const [yMin, yMax] = yRange;

  const percent = (inputY - yMin) / (yMax - yMin);
  const outputX = percent * (xMax - xMin) + xMin;

  return outputX;
};