/*[[
  Name := DiNapoli Deterend Price Oscillator
  Author := Copyright © 2005, a1cor.
  Separate Window := Yes
  First Color := Red
  First Draw Type := Line
  Use Second Data := Yes
  Second Color := Blue
  Second Draw Type := Line
]]*/

Input    : MAPeriod1(3),MAPeriod2(7);
Variable : shift(0), dpo1(0), dpo2(0);
Variables : loopbegin(0), first(True), prevbars(0);

SetLoopCount(0);

// check for additional bars loading or total reloading
If Bars < prevbars Or Bars-prevbars>1 Then first = True;

prevbars = Bars;

// loopbegin prevent counting of counted bars exclude current
If first Then Begin
  if MAPeriod2 > MAPeriod1 then
    loopbegin = Bars-MAPeriod2-1
  else
    loopbegin = Bars-MAPeriod1-1;
  If loopbegin < 0 Then Exit; // not enough bars for counting
  first = False; // this block is to be evaluated once only
End;

// Detrend Price Oscillator
loopbegin = loopbegin+1; // current bar is to be recounted too
For shift = loopbegin Downto 0 Begin
  dpo1=C[shift]-iMAEx(MAPeriod1,MODE_SMA,0,PRICE_CLOSE,shift);
  dpo2=C[shift]-iMAEx(MAPeriod2,MODE_SMA,0,PRICE_CLOSE,shift);
  SetIndexValue (shift,dpo1);
  SetIndexValue2(shift,dpo2);
  loopbegin = loopbegin-1; // prevent to previous bars recounting
End;