This is a modified version of Bill Williams' Accelerator. The Accelerator measures the difference between the Awesome Oscillator(another Williams indicator) and its 5 day SMA.
This script plots 2 accelerators rather than 1. Users can define the lengths of the fast and slow SMA's used in the Awesome Oscillator calculation by adjusting the options in the input menu.
We set the default the lengths of the fast and slow SMA's used in the first Awesome Oscillator calculation as 34 and 7 periods. Then to find the Accelerator Oscillator, the difference between the Awesome Oscillator and its 7 period SMA is calculated. The second Accelerator uses shorter window lengths than the first. The fast SMA length is 5 by default and the slow SMA length is 18. Finally, the length of the Awesome Oscillator SMA used to calculate the second Accelerator Oscillator is 3.
By utilizing two Accelerator Oscillators with increasingly shorter window lengths, this indicator identifies changes in momentum very well.
The red and green histogram represents the first Accelerator Oscillator. It is green when the Accelerator is increasing and red when it is decreasing. I found this layout to be more practical than the standard, which plots the AC as green when it is greater than 0 and red when less than zero. The second Accelerator Oscillator is plotted as the bright green and pink circle line. It uses the same coloring conditions as above.