Regression Line (OLS) w/Residual Bands - Beasley Savage

Plots linear regression "line of best fit" for a given source and length. Also plots the standard deviation of residuals as upper and lower bands. For some reason it's not plotting the lines exactly where the values are, so I wouldn't recommend using it as a purely visual indicator, but it could be used in strategies. A quick implementation of a strategy buying when the close crossed over the lower band and selling when close crossed under the upper band resulted in ~60-70% trade accuracy, not taking into account commission/slippage.

If anyone knows how to fix the lines not plotting accurately please let me know :)