How are iSAR values read?

Create an iSAR handle with symbol, timeframe, step and maximum, then read buffer 0 with CopyBuffer. Check the handle and returned count. This example uses chronological arrays throughout; ArraySetAsSeries(true) is not a universal requirement. The forming SAR dot can change as the bar develops.

Which signals and filters does this indicator implement?

A completed bar changes the SAR-versus-close side, the close must also be on the matching side of the EMA, and ATR must be at least 80% of its rolling average. That is weaker than requiring ATR above its average. The filters are explicit conditions, not proven improvements in win rate.

Does this indicator manage trailing stops?

No. It draws SAR dots and filtered arrows, with no OrderSend or position management. An EA using a SAR reference would need direction-aware stop checks, a rule that prevents loosening, actual position tickets, broker stop constraints and result handling. CTrade.PositionModify or TRADE_ACTION_SLTP are MQL5 options; there is no standalone PositionModify function.

Are the acceleration defaults optimal?

No performance evidence establishes that. Changing step or maximum changes the computed SAR path; the effect on a complete strategy also depends on entry, exit, costs and data. The default values are illustrative, not a recommendation for a pair or timeframe.

How can an EA read the filtered output?

Compile the indicator, create an iCustom handle with matching input order, then read buffer 3 at shift 1 for the latest completed-bar event: 1 for an up flip, -1 for a down flip, 0 for no filtered flip. It is an event marker, not a persistent trend state. Buffers 1 and 2 contain arrow prices or EMPTY_VALUE.

What changes after a history update?

The sample recalculates the full available history and can reflect corrected data or changed inputs. Signals exclude the current forming bar, but that does not guarantee historical values can never change. This implementation favors clarity over incremental efficiency and contains no alerts or early-exit mechanism.

Complete .mq5 source code

Parabolic SAR MQL5 Indicator: Trailing Stop & Trend Reversal Detection

Implement iSAR-based dots and completed-bar flip markers in a custom MQL5 indicator. The example adds an EMA condition and an explicit ATR gate, exposes signal buffers for iCustom and keeps drawing separate from trade execution. No reproducible backtest supports a claimed performance improvement.

Build a custom MT5 indicator View the MQL5 code

How the indicator signal works

Calculation and signal conditions

A completed bar produces an up marker when SAR changes from above the close to at or below it, the close is above the EMA, and ATR is at least 80% of its moving average. The reverse relation produces a down marker. All calculations use the chart timeframe and aligned chronological arrays; arrows never use the forming bar.

Interpretation and limitations

The indicator does not submit orders, move a stop, close positions or forecast an imminent flip from shrinking SAR distance. A plotted SAR level is only a reference for a separately defined EA exit rule. Neither a dot change nor the optional filter concept establishes a profitable reversal or a protected loss limit.

MQL5 Custom Indicator Code

#property strict
#property indicator_chart_window
#property indicator_buffers 4
#property indicator_plots 4
#property indicator_type1 DRAW_ARROW
#property indicator_color1 clrDodgerBlue
#property indicator_label1 "SAR"
#property indicator_type2 DRAW_ARROW
#property indicator_color2 clrLimeGreen
#property indicator_label2 "Filtered up flip"
#property indicator_type3 DRAW_ARROW
#property indicator_color3 clrTomato
#property indicator_label3 "Filtered down flip"
#property indicator_type4 DRAW_NONE
#property indicator_label4 "Completed-bar signal"
input double InpSARStep=0.02;
input double InpSARMaximum=0.2;
input int InpEMAPeriod=50;
input int InpATRPeriod=14;
input int InpATRMAPeriod=20;
double sar[],up[],down[],direction[];
int hs=INVALID_HANDLE,he=INVALID_HANDLE,ha=INVALID_HANDLE;
int OnInit()
{
   if(InpSARStep<=0 || InpSARMaximum<InpSARStep || InpEMAPeriod<=0
      || InpATRPeriod<=0 || InpATRMAPeriod<=0) return INIT_PARAMETERS_INCORRECT;
   SetIndexBuffer(0,sar,INDICATOR_DATA); SetIndexBuffer(1,up,INDICATOR_DATA);
   SetIndexBuffer(2,down,INDICATOR_DATA); SetIndexBuffer(3,direction,INDICATOR_DATA);
   ArraySetAsSeries(sar,false); ArraySetAsSeries(up,false);
   ArraySetAsSeries(down,false); ArraySetAsSeries(direction,false);
   PlotIndexSetInteger(0,PLOT_ARROW,159);
   PlotIndexSetInteger(1,PLOT_ARROW,241); PlotIndexSetInteger(2,PLOT_ARROW,242);
   int warmup=MathMax(InpEMAPeriod,InpATRPeriod+InpATRMAPeriod);
   for(int p=1;p<4;p++) PlotIndexSetInteger(p,PLOT_DRAW_BEGIN,warmup);
   IndicatorSetString(INDICATOR_SHORTNAME,"PSAR("+DoubleToString(InpSARStep,3)+","+DoubleToString(InpSARMaximum,3)+")");
   hs=iSAR(_Symbol,_Period,InpSARStep,InpSARMaximum);
   he=iMA(_Symbol,_Period,InpEMAPeriod,0,MODE_EMA,PRICE_CLOSE);
   ha=iATR(_Symbol,_Period,InpATRPeriod);
   return hs==INVALID_HANDLE || he==INVALID_HANDLE || ha==INVALID_HANDLE?INIT_FAILED:INIT_SUCCEEDED;
}
void OnDeinit(const int reason)
{
   if(hs!=INVALID_HANDLE) IndicatorRelease(hs);
   if(he!=INVALID_HANDLE) IndicatorRelease(he);
   if(ha!=INVALID_HANDLE) IndicatorRelease(ha);
}
int OnCalculate(const int rates_total,const int prev_calculated,
 const datetime &time[],const double &open[],const double &high[],const double &low[],
 const double &close[],const long &tick_volume[],const long &volume[],const int &spread[])
{
   int warmup=MathMax(InpEMAPeriod,InpATRPeriod+InpATRMAPeriod);
   if(rates_total<=warmup+1) return 0;
   ArraySetAsSeries(close,false); ArraySetAsSeries(high,false); ArraySetAsSeries(low,false);
   double ema[],atr[]; ArraySetAsSeries(ema,false); ArraySetAsSeries(atr,false);
   if(CopyBuffer(hs,0,0,rates_total,sar)!=rates_total
      || CopyBuffer(he,0,0,rates_total,ema)!=rates_total
      || CopyBuffer(ha,0,0,rates_total,atr)!=rates_total) return prev_calculated;
   // Full-history calculation keeps all inputs in chronological order.
   ArrayInitialize(up,EMPTY_VALUE); ArrayInitialize(down,EMPTY_VALUE);
   ArrayInitialize(direction,0);
   for(int i=warmup;i<rates_total-1;i++) // Exclude the forming bar.
   {
      double average=0;
      for(int j=0;j<InpATRMAPeriod;j++) average+=atr[i-j];
      average/=InpATRMAPeriod;
      if(average<=0 || atr[i]<0.8*average || sar[i]<=0 || sar[i-1]<=0) continue;
      bool wasAbove=sar[i-1]>close[i-1],nowAbove=sar[i]>close[i];
      double offset=MathMax(high[i]-low[i],_Point)*0.3;
      if(wasAbove && !nowAbove && close[i]>ema[i])
         { up[i]=low[i]-offset; direction[i]=1; }
      else if(!wasAbove && nowAbove && close[i]<ema[i])
         { down[i]=high[i]+offset; direction[i]=-1; }
   }
   return rates_total;
}

Copy this code into MetaEditor, save it in the MQL5/Indicators folder, and compile with F7.

Change the settings or add your own signal filter

Describe the inputs, buffers, alerts, visual style, or confirmation filter you want. Pineify generates editable MQL5 source code that you can inspect and compile in MetaEditor.

Generate custom MQL5 code Read the MT5 testing guide

Frequently Asked Questions

Related MQL5 pages

Moving Average Mql5 Indicator→Atr Indicator Mql5→Mql5 Trend Following Ea→

Risk and testing note

These educational examples require independent compilation and testing. A compile pass or an illustrative setting does not establish execution correctness or profitability. Any reported performance must be supported by reproducible data and test settings; past results do not predict future returns. Trading involves significant risk of loss. This content is not financial advice.