The Aroon Oscillator Indicator

Aroon Indicators by Tushar Chande
For interpretation of the Aroon indicators refer to the article Tushar Chande "Time Price Oscillator" in September, 95 Technical analysis of stocks and Commodities magazine.
The Aroon down:
100 * (14 - ((If (Ref (L, -1) = LLV (L, 14), 1, If (Ref (L, -2) = LLV (L, 14), 2, If (Ref (L , - 3) =
LLV (L, 14), 3, If (Ref (L, -4) = LLV (L, 14), 4, If (Ref (L, -5) = LLV (L, 14), 5, If (Ref (L, -6) =
LLV (L, 14), 6, If (Ref (L, -7) = LLV (L, 14), 7, If (Ref (L, -8) = LLV (L, 14), 8, If (Ref (L, -9) =
LLV (L, 14), 9, If (Ref (L, -10) = LLV (L, 14), 10, If (Ref (L, -11) = LLV (L, 14), 11, If (Ref (L, -12) =
LLV (L, 14), 12, If (Ref (L, -13) = LLV (L, 14), 13, If (Ref (L, -14) = LLV (L, 14), 14, 0)) ))))))))))))))) / 14
The Aroon up:
100 * (14 - ((If (Ref (H, -1) = HHV (H, 14), 1, If (Ref (H, -2) = HHV (H, 14), 2, If (Ref (H , - 3) =
HHV (H, 14), 3, If (Ref (H, -4) = HHV (H, 14), 4, If (Ref (H, -5) = HHV (H, 14), 5, If (Ref (H, -6) =
HHV (H, 14), 6, If (Ref (H, -7) = HHV (H, 14), 7, If (Ref (H, -8) = HHV (H, 14), 8, If (Ref (H, -9) =
HHV (H, 14), 9, If (Ref (H, -10) = HHV (H, 14), 10, If (Ref (H, -11) = HHV (H, 14), 11, If (Ref (H, -12) =
HHV (H, 14), 12, If (Ref (H, -13) = HHV (H, 14), 13, If (Ref (H, -14) = HHV (H, 14), 14, 0)) ))))))))))))))) / 14

The Aroon Oscillator = Aroon up - Aroon down.
** Up and Down Aroon indicators to be plotted in the same inner window.
** They are constructed using 14 periods, you can change this by replacing each entry of 14 with the desired period.