Convert number from one scale to another

scale.cljc

(defn scale
  "Converts the number `x` from the scale `[old-min old-max]` to the scale
   `[new-min new-max]`."
  [x [old-min old-max] [new-min new-max]]
  (let [old-range (- old-max old-min)
        new-range (- new-max new-min)]
    (+ (/ (* (- x old-min) new-range) old-range) new-min)))

scale.js

function scale(x, oldMin, oldMax, newMin, newMax){
  let oldRange = oldMax - oldMin;
  let newRange = newMax - newMin;
  return ((newRange * (x - oldMin)) / oldRange) + newMin;
}