The polarity in this calculation is determined by divergence between a fast and slow Dynamic.
Your current resolution's polarity is the top row, the rows below are are for higher timeframes of your choice.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.