I'm having a couple of issues with RSI so plan to post two backtests.
This one is straightforward. It adds SPY as an equity and defines a 14 day RSI. On an EOD routine it logs the price and RSI value.
Note the negative RSI values around 12/24 and the value over 100 on 1/22. The range for RSI is 0-100 so how can this be? Is there something wrong with the way I am defining it?