afl amibroker AC Oscillator

/* Exploration, System and Indicator */
//    Author: Steve Wiser
//   Email address: slwiserr@erols.com
//   May 5, 2001 */

/*

If the momentum is with us (it is above zero and we are buying,
or below zero and we are selling), we want to enter aggressively and we need only two green
bars for a buy (two red bars for a sell). If the momentum is against us (it is below zero and we
are buying, or above zero and we are selling), we want confirmation so we require one extra
bar. In this case, we would require three red bars to sell above the zero line and three green
bars to buy below the zero line.

1. A buy signal is created when there are two consecutive histogram bars with higher highs
than the most recent lowest low (a down peak).
2. A buy stop is placed one tick above the high of the price bar, which corresponds (in the
same time frame) to the second higher high.
3. A second buy signal cannot be created until the histogram moves at least one bar lower,
creating a red bar. A new buy signal can then be created after two higher (green) bars.
4. In the software, this is easy to spot because it requires at least one red bar followed by two
green bars on the AC histogram.

These are the AC rules for buying when the histogram is "crossing" the zero line from below
to above (negative to positive):
1. A buy signal is created if the AC histogram down peak is below the zero line and crosses
the line on the second or third bar after the down peak. When that happens and the current
"indicator" bar in the histogram is above the zero line, you need only two higher highs.
2. IT IS IMPORTANT TO UNDERSTAND THAT CROSSING THE ZERO LINE IS NOT A
SIGNAL ON THE AC HISTOGRAM. (Crossing the zero line is a signal only on the AO
chart.)
3. Crossing the zero line on the histogram chart only changes the number of green bars (higher
highs) that you need for a buy signal. The reason behind reducing the number of histogram
bars after crossing the zero line is that the momentum is now in your favor and you want to
get in OR add to your position as quickly as possible.


With the AC, you cannot have a buy if the bar is red, and you cannot have a sell if
the bar is green.
Important: Perform the sell/buy in the bar following the signal bar (the current bar).
You cannot have a sell signal with a current green bar on the AC histogram.
You cannot have a buy signal with a current red bar on the AC histogram.
*/

//outsidebar = Outside();
//insidebar = H <= Ref(H,-1) AND L >= Ref(L,-1);
//upbar = H > Ref(H,-1) AND L >= Ref(L, -1);
//downbar = L < Ref(L,-1) AND H <= Ref(H,-1);
//barcolor=IIf(outsidebar, 1,
//               IIf(downbar,   4,
//               IIf(upbar,        5,
//               IIf(insidebar,6, 0 ) ) ) );


var1=MA( (H+L)/2 , 34);
var2=MA( (H+L)/2,5);
var3=var2-var1;
var4=var3-MA(var3,5);
up = Var4 > Ref(Var4,-1);
down = Var4 < Ref(Var4,-1);
/*
Graph0=var4;
Graph0Style=2+4;
Graph1=Wilders(var4,5);
Graph1Style=5;
Graph0Name = "AC";
Graph0BarColor = IIf(up, colorGreen, colorRed);
*/
Barcolor=IIf(up, colorGreen, colorRed);
Plot(var4,"AC",Barcolor,styleHistogram|styleNoLabel,Null,Null,0,0,3);

//3 bars buy when in positive territory:
AllAbove0 = Ref(Var4,-3) > 0 AND Ref(Var4,-2) > 0 AND Ref(Var4,-1) > 0;
SellA = Ref(up,-3) AND Ref(down,-2) AND Ref(down,-1) AND down AND AllAbove0;

//2 bars sell. If in negative territory or crossed below 0:
AllBelow0 = Ref(Var4,-3) < 0 AND Ref(Var4,-2) < 0 AND Ref(Var4,-1) > 0;
CrossBelow0 = (Ref(Var4,-2) > 0 AND Ref(Var4,-1) < 0) OR (Ref(Var4,-1) > 0 AND Var4 < 0);
SellB = Ref(up,-2) AND Ref(down,-1) AND down AND (AllBelow0  OR CrossBelow0);

CrossAbove0 = (Ref(Var4,-2) < 0 AND Ref(Var4,-1) > 0) OR (Ref(Var4,-1) < 0 AND Var4 > 0);
//3 bars buy when in negative territory:
BuyA = Ref(down,-3) AND Ref(up,-2) AND Ref(up,-1) AND up AND AllBelow0;
//2 bars buy. If in positive territory or crossed above 0:
BuyB = Ref(down,-2) AND Ref(up,-1) AND up AND (AllAbove0 OR CrossAbove0);

Buy = BuyA OR BuyB;
Sell = SellA OR SellB;

PlotShapes( IIf(Buy ,shapeUpArrow,0) ,colorGreen, 0, IIf(Var4 < 0, Var4, 0),-12);
PlotShapes( IIf(Sell ,shapeDownArrow,0) ,colorRed, 0, IIf(Var4 < 0, Var4, 0),12);

Tick =
    IIf( C <   200, 1,
    IIf( C >=  200 AND C <  500,  2,
    IIf( C >= 500 AND C < 2000,5,
    IIf( C >= 2000 AND C < 5000,10,
    IIf( C >= 5000, 25, 0 )))));
//Commentary
WriteIf(Buy, "Place Buy Stop to buy 1 unit if price rises to " + WriteVal(H+Tick)+" or higher. (AC+)",
WriteIf(Sell, "Place Sell Stop to sell 1 unit if price falls to " + WriteVal(L-Tick)+" or lower. (AC-)",""));