/*[[
	Name := choppy market index
	Author := Copyright © 2004, Nick Bilak
	Link := 
	Separate Window := Yes
	First Color := Red
	First Draw Type := Line
	Use Second Data := Yes
	Second Color := DimGray
	Second Draw Type := Line
	Second Symbol := 218
]]*/
Inputs : cperiod(30),trigger(20);
Variables : shift(0), loopbegin(0), first(True), prevbars(0);
Variables : MAValue(0);
SetLoopCount(0);
// initial checkings
// check for additional bars loading or total reloading
If Bars < prevbars Or Bars-prevbars>1 Then first = True;
prevbars = Bars;
If first Then Begin
	// loopbegin prevent couning of counted bars exclude current
	loopbegin = Bars-cperiod-1;
	If loopbegin < 0 Then Exit;      // not enough bars for counting
	first = False;
End;

// moving average
loopbegin = loopbegin+1;             // current bar is to be recounted too
For shift = loopbegin Downto 0 Begin
	MAValue = (Abs(Close[shift] - Close[shift+cperiod])/(HIGH[Highest(MODE_High,shift+cperiod,cperiod)] - LOW[Lowest(MODE_Low,shift+cperiod,cperiod)])*100);
	SetIndexValue(shift,MAValue);
	SetIndexValue2(shift,Trigger);
	loopbegin = loopbegin-1;         // prevent to previous bars recounting
End;