phpjs/experimental/datetime/date_isodate_set.js

php.js offers community built php functions in javascript

function date_isodate_set(dt, year, week, day) {
  // http://kevin.vanzonneveld.net
  // +   original by: Brett Zamir (http://brett-zamir.me)
  // *     example 1: var dt = date_create();
  // *     example 1: date_isodate_set(dt, 2008, 2, 5);
  // *     returns 1: {}

  return dt.setISODate(year, week, day);
}