Previous High/Low/Open/Close

You have probably noted that the Open of the day, the Close of yesterday, and the High and Low of the current day are important support/resistance points.

It is one thing to write an indicator that would plot the High and Low for the current day. However, on a tick through 5-minute chart that is set to display only a small slice of the day at a time, this could cause the chart to zoom way out if there has been a large move from the High to the Low for the day. In other words, the chart may be so far zoomed out that you can hardly see any detail. In comes our auto-zoom feature to show the High and Low for today and yesterday.