You can apply an indicator (such as a Moving Average) or strategy not only to price data, but to another indicator as well. This opens a world of possibilities for technical analysis as well as finding new opportunities to trade.
There are three ways to do it:
1. Click the "More" button (the three horizontal dots) next to the title of the indicator you wish to use as an external input, select "Add Indicator/Strategy on…" and then choose the indicator or strategy that will be using the first indicator as an input.
2. Right-click on an indicator's plot. Then select "Add Indicator/Strategy on…"
3. Add the external input from a script's "Settings/Inputs" tab. To do this, first make sure both scripts are loaded on your chart. Click the "Settings" cog next to the title of the indicator or strategy to which you want to connect an external input. Then, from the "Inputs" tab, click on the source dropdown and select a plot from the other indicator you want to use as an external input.
For this functionality to work, the indicator or strategy to which an external input is connected must contain only one input() call using the input.source type and the external input used must originate from a study.
Please note that not all indicators can be calculated based on another indicator due to various technical nuances.