OPEN-SOURCE SCRIPT

Harris RSI

This is a variation of Wilder's RSI that was altered by Michael Harris.

CALCULATION

The average change of each of the length's source value is compared to the more recent source value.
The average difference of both positive or negative changes is found.
The range of 100 is divided by the divided result of the average incremented and decremented ratio plus one.
This result of the above is subracted from the range value of 100

I have added some signals and filtering options with moving averages:

Trend OB/OS: Uptrend after above Overbought Level. Downtrend after below Oversold Level\n(For the traditional RSI OB=60 and OS=40 is used)
OB/OS: When above Overbought, or below oversold
50-Cross: Above 50 line is uptrend, below is downtrend
Direction: Moving up or down
RSI vs MA: RSI above MA is an uptrend, RSI below MA is a downtrend

The signals I added are just some potential ideas, always backtest your own strategies.