Quadratic regression is the process of finding the equation of a parabola that best fits the set of data being analyzed.
In this study, first a quadratic regression curve is calculated, then the slope of the curve is calculated and plotted.
Custom bar colors are included. The color scheme is based on whether the slope is positive or negative, and whether it is increasing or decreasing.
-> Migrated to v4.
-> Updated QRS function for improved performance.
-> Added an offset parameter to the script, which will base current value on offset values of the extrapolated QR curve.
-> Included some experimental signal processing procedures:
- Added an option to normalize the oscillator scale using RMS.
- Added an optional compression algorithm to the script. This can be used to reduce transients (short duration, high amplitude values) by a specified level of intensity.
-> Updated color scheme.
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.
To answer your question, QRS requires two inputs, x and t, which correspond to src and per in the script, respectively. smper is the sampling period for exponential smoothing of the QRS outside the function's definitions. n is the current bar number.