This is a demo tutorial. While there is no step-by-step commentary available (yet), the live demo below is fully functional. Feel free to open it for full source code.
This demo shows how we can use axis'
getSeriesDataItem() method to find the first and last data items when an XY chart is zoomed.
See the Pen
Find out first and last data items of the XYChart by amCharts team (@amcharts)