//+--------------------------------------------------------------------------+
//|                                                     Laguerre_MinusDi.mq5 |
//|                         Copyright © 2005, Emerald King / transport_david | 
//| http://finance.groups.yahoo.com/group/MetaTrader_Experts_and_Indicators/ | 
//+--------------------------------------------------------------------------+
#property copyright "Copyright © 2007, Emerald King / transport_david"
#property link "http://finance.groups.yahoo.com/group/MetaTrader_Experts_and_Indicators/"
//--- indicator version
#property version   "1.00"
//--- drawing the indicator in a separate window
#property indicator_separate_window
//--- one buffer is used for calculation and drawing of the indicator
#property indicator_buffers 1
//--- one plot is used
#property indicator_plots   1
//+----------------------------------------------+
//|  Indicator drawing parameters                |
//+----------------------------------------------+
//--- drawing the indicator as a line
#property indicator_type1   DRAW_LINE
//--- Red color is used as the color of the indicator line
#property indicator_color1  clrRed
//--- Indicator line is a solid one
#property indicator_style1 STYLE_SOLID
//--- indicator line width is 2
#property indicator_width1 2
//+----------------------------------------------+
//| Parameters of displaying horizontal levels   |
//+----------------------------------------------+
#property indicator_level2 0.75
#property indicator_level3 0.45
#property indicator_level4 0.15
//--- blue color is used for the horizontal level line
#property indicator_levelcolor clrBlue
//--- Short dot-dash is used for the horizontal level line
#property indicator_levelstyle STYLE_DASHDOTDOT
//+----------------------------------------------+
//|  declaring constants                         |
//+----------------------------------------------+
#define RESET  0 // the constant for getting the command for the indicator recalculation back to the terminal
//+----------------------------------------------+
//| Indicator input parameters                   |
//+----------------------------------------------+
input uint ADXPeriod=14;
input double gamma=0.764;
//+----------------------------------------------+
//--- declaration of a dynamic array that
//--- will be used as an indicator buffer
double ExtLineBuffer[];
//--- declaration of integer variables of data starting point
int min_rates_total;
//--- declaration of integer variables for the indicators handles
int ADX_Handle;
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+  
int OnInit()
  {
//--- initialization of variables of the start of data calculation
   min_rates_total=int(ADXPeriod);
//--- getting the handle of the iADX indicator
   ADX_Handle=iADX(NULL,0,ADXPeriod);
   if(ADX_Handle==INVALID_HANDLE)
     {
      Print(" Failed to get the handle of the iADX indicator");
      return(INIT_FAILED);
     }
//--- set ExtLineBuffer dynamic array as indicator buffer
   SetIndexBuffer(0,ExtLineBuffer,INDICATOR_DATA);
//--- indexing elements in the buffer as in timeseries
   ArraySetAsSeries(ExtLineBuffer,true);
//--- initializations of a variable for the indicator short name
   string shortname;
   StringConcatenate(shortname,"Laguerre_MinusDi(",ADXPeriod,", ",gamma,")");
//--- create a label to display in the Data Window
   PlotIndexSetString(0,PLOT_LABEL,shortname);
//--- creation of the name to be displayed in a separate sub-window and in a pop up help
   IndicatorSetString(INDICATOR_SHORTNAME,shortname);
//--- determining the accuracy of the indicator values
   IndicatorSetInteger(INDICATOR_DIGITS,2);
//--- restriction to draw empty values for the indicator
   PlotIndexSetDouble(0,PLOT_EMPTY_VALUE,EMPTY_VALUE);
//--- shifting the start of drawing of the indicator 1
   PlotIndexSetInteger(0,PLOT_DRAW_BEGIN,min_rates_total);
//--- initialization end
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int OnCalculate(const int rates_total,    // number of bars in history at the current tick
                const int prev_calculated,// amount of history in bars at the previous tick
                const datetime &time[],
                const double &open[],
                const double& high[],     // price array of maximums of price for the calculation of indicator
                const double& low[],      // price array of price lows for the indicator calculation
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
  {
//--- checking if the number of bars is enough for the calculation
   if(BarsCalculated(ADX_Handle)<rates_total || rates_total<min_rates_total) return(RESET);
//--- declarations of local variables 
   int to_copy,limit,bar;
   double L0,L1,L2,L3,L0A,L1A,L2A,L3A,LDMIM=0,CU,CD,DMIM[];
//--- declarations of static variables for storing real values of coefficients
   static double L0_,L1_,L2_,L3_,L0A_,L1A_,L2A_,L3A_;
//--- calculation of the starting number for the cycle of recalculation of bars
   if(prev_calculated>rates_total || prev_calculated<=0) // checking for the first start of the indicator calculation
     {
      limit=rates_total-min_rates_total-1; // starting index for the calculation of all bars
      //--- the starting initialization of calculated coefficients
      L0_ = 0.0;
      L1_ = 0.0;
      L2_ = 0.0;
      L3_ = 0.0;
      L0A_ = 0.0;
      L1A_ = 0.0;
      L2A_ = 0.0;
      L3A_ = 0.0;
     }
   else limit=rates_total-prev_calculated; // starting index for the calculation of new bars
   to_copy=limit+1;
//--- copy newly appeared data in the arrays
   if(CopyBuffer(ADX_Handle,MINUSDI_LINE,0,to_copy,DMIM)<=0) return(RESET);
//--- apply timeseries indexing to array elements  
   ArraySetAsSeries(DMIM,true);
//--- Restore values of the variables
   L0 = L0_;
   L1 = L1_;
   L2 = L2_;
   L3 = L3_;
   L0A = L0A_;
   L1A = L1A_;
   L2A = L2A_;
   L3A = L3A_;
//--- main calculation loop of the indicator
   for(bar=limit; bar>=0 && !IsStopped(); bar--)
     {
      L0A = L0;
      L1A = L1;
      L2A = L2;
      L3A = L3;
      //---
      L0 = (1 - gamma) * DMIM[bar] + gamma * L0A;
      L1 = - gamma * L0 + L0A + gamma * L1A;
      L2 = - gamma * L1 + L1A + gamma * L2A;
      L3 = - gamma * L2 + L2A + gamma * L3A;
      //---
      CU = 0;
      CD = 0;
      //--- 
      if(L0 >= L1) CU  = L0 - L1; else CD  = L1 - L0;
      if(L1 >= L2) CU += L1 - L2; else CD += L2 - L1;
      if(L2 >= L3) CU += L2 - L3; else CD += L3 - L2;
      //---
      if(CU+CD!=0) LDMIM=CU/(CU+CD);
      //--- initialization of the cell of the indicator buffer by the obtained value of LRSI
      ExtLineBuffer[bar]=LDMIM;
      //--- save values of the variables before running at the current bar
      if(bar==1)
        {
         L0_ = L0;
         L1_ = L1;
         L2_ = L2;
         L3_ = L3;
         L0A_ = L0A;
         L1A_ = L1A;
         L2A_ = L2A;
         L3A_ = L3A;
        }
     }
//---     
   return(rates_total);
  }
//+------------------------------------------------------------------+