VAcc_01_en

//------------------------------------------------------------------
//  VAcc_01.mq5
//  victorg
//------------------------------------------------------------------
#property copyright   ""
#property link        ""
#property description "VAcc"
//--- indicator settings
#property indicator_separate_window
#property indicator_level1 0.0
#property indicator_levelcolor DarkSlateGray
#property indicator_levelwidth 0
#property indicator_levelstyle STYLE_DOT 
#property indicator_buffers 1
#property indicator_plots   1
#property indicator_type1   DRAW_LINE
#property indicator_color1  DodgerBlue
#property indicator_label1  "VAcc"
//--- input parameters
input int InpAccPeriod=3;  // Acc period (1...100)
input int InpMAPeriod=5;   // MA period  (2...100)
input int InpNHistory=255; // N History  (32...1024)
//--- indicator buffers
double    ExtOutBuffer[];
//--- global variable
int       ExtPeriodAcc;
int       ExtPeriodMA;
int       ExtNHistory;
double    P1,P2;
//------------------------------------------------------------------
// Custom indicator initialization function
//------------------------------------------------------------------
void OnInit()
  {
//--- check for input value
  if(InpAccPeriod<1 || InpAccPeriod>100)
    {
     ExtPeriodAcc=3;
     printf("Incorrect input parameter InpAccPeriod = %d. Indicator will use value %d for calculations.",InpAccPeriod,ExtPeriodAcc);
    }
  else ExtPeriodAcc=InpAccPeriod;
  if(InpMAPeriod<2 || InpMAPeriod>100)
    {
     ExtPeriodMA=3;
     printf("Incorrect input parameter InpMAPeriod = %d. Indicator will use value %d for calculations.",InpMAPeriod,ExtPeriodMA);
    }
  else ExtPeriodMA=InpMAPeriod;   
  P1=2.0/(ExtPeriodMA+1); P2=1.0-P1;
  if(InpNHistory<32 || InpNHistory>1024)
    {
     ExtNHistory=255;
     printf("Incorrect input parameter InpNHistory = %d. Indicator will use value %d for calculations.",InpNHistory,ExtNHistory);
    }
  else ExtNHistory=InpNHistory;     
//--- indicator buffers mapping
  SetIndexBuffer(0,ExtOutBuffer,INDICATOR_DATA);
//--- set indexation like time series
   ArraySetAsSeries(ExtOutBuffer,true);
//---
  IndicatorSetInteger(INDICATOR_DIGITS,_Digits);
//--- name for DataWindow and indicator subwindow label
  string short_name="VAcc("+string(ExtPeriodAcc)+")";
  IndicatorSetString(INDICATOR_SHORTNAME,short_name);
  PlotIndexSetString(0,PLOT_LABEL,short_name);
//--- initialization done
  }
//------------------------------------------------------------------
// VAcc                                               
//------------------------------------------------------------------
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 &TickVolume[],
                const long &Volume[],
                const int &Spread[])
  {
  int i;

  ArraySetAsSeries(Close,true);
  PlotIndexSetInteger(0,PLOT_DRAW_BEGIN,Bars(Symbol(),0)-ExtNHistory);

  ExtOutBuffer[ExtNHistory+1]=0.0;
  for(i=ExtNHistory;i>=0;i--)ExtOutBuffer[i]=MathLog(Close[i]/Close[i+ExtPeriodAcc])*P1+ExtOutBuffer[i+1]*P2;
  for(i=1;i<ExtNHistory;i++)ExtOutBuffer[i]=ExtOutBuffer[i]*P1+ExtOutBuffer[i-1]*P2;
  for(i=ExtNHistory-1;i>=0;i--) ExtOutBuffer[i]=ExtOutBuffer[i]*P1+ExtOutBuffer[i+1]*P2;
  for(i=1;i<ExtNHistory;i++)ExtOutBuffer[i]=ExtOutBuffer[i]*P1+ExtOutBuffer[i-1]*P2;

  return(rates_total);

  }
//------------------------------------------------------------------