问题
it is possible to increase only the array timelineData[n] without for, while loops, otherwise it would repeat the (document.getElementById('timeline') in the page!
timeline = new vis.Timeline(document.getElementById('timeline'), timelineData[n], timelineOptions);
timelineData[n] it is an Array that contains values that I would need to represent a graphic timeline thanks!
来源：https://stackoverflow.com/questions/60252383/javascript-and-vis-js-increase-only-array-in-document-getelementbyid-without-fo