Timeseries in DoEasy library (part 50): Multi-period multi-symbol standard indicators with a shift

MetaTrader 5 — Examples | 1 December 2020, 14:27

3 513

Artyom Trishkin

Concept

Over the course of several articles in a row, step by step we have created a functionality for displaying standard indicators on the current symbol/period chart in the multi-symbol multi-period indicator mode. Yet, not all the standard indicators may be displayed in such a mode; but today, let’s digress from the subject of standard indicator conversion into multi-modes.
No, we will not do something different - everything will be within the frames of the same topic, but... If we try to create a multi-period indicator which line is shifted on the current symbol chart, we will fail. The reason is that until now, we have used the default value to be set in class constructor of a buffer object as the shift of indicator line. And it is equivalent to zero. And if we simply set a shift of multi-period indicator line as equivalent to the value of a shift of standard indicator line, we also will fail: the line will shift, but only within those bars for which the standard indicator line is shifted.
Cause: for correct display of multi-period indicator line it is required to calculate how many bars of the current chart are contained within one bar of that chart period in which the standard indicator is calculated, and how many bars the line will be shifted for. In other words, if a standard indicator is calculated on H4 chart and we display it on H1 chart we must draw one bar of H4 on four bars of H1. The same concerns shift: if standard indicator line is shifted for one bar on H4 chart, we must shift it for four bars on H1 chart.

And this is not the end. The same is when filling in the calculated buffer array we must consider a shift of standard indicator line in the buffer object; and this shift must specify the initial reference point of a number of the bars which we copy from the source array of standard indicator to the recipient array of the buffer object we created.

Upon implementation and at observation of the above specified rules we will be able to correctly display the standard indicator in the multi-period mode with line shift.

Let me point out that not all the standard indicators at once yielded to such sufficiently simple conversion into a multi-period mode with line shift. For now, we fail to display in the multi-period mode those indicators which lines in authors’ idea are originally drawn with a shift (Gator Oscillator and Ichimoku Kinko Hyo). Whereas, Alligator indicator easily yielded to conversion. I think this is caused by the fact that in the Alligator indicator each line being drawn is set with its own shift. We display them with calculated shift and everything is displayed correctly and Gator and Ichimoku indicators use originally shifted lines for their calculation. In any case, we will find the cause and create those indicators as multi-period and multi-symbol ones. And meanwhile, in order not to dwell on a search for causes (I will do it simultaneously with development) - I will create further library functionality. The more so, very soon it will become more interesting - inclusion of standard indicator data into bar objects of timeseries class. This will allow to quickly search any combinations of any indicators at any chart symbol/period.

Along with implementation of display of standard indicators with line shift, today we will create general methods for preparation and display of standard methods in multi-modes. For the time being, for each standard indicator their own display methods have been implemented. Gradual creation of multi-symbol multi-period indicators clearly suggests what actually is completely the same in all the particular methods. Today, we will perform something which is possible to do in a single universal method working with each of the standard indicators. This will greatly simplify and reduce code size of indicator buffer collection class.

Finally, today from the final indicator we will remove calculation and setting of standard indicator levels in subwindow and of capacity of standard indicator line data being displayed in terminal data window. Remove this calculation to a file of library service functions and call it from the test indicator. This will simplify the final code and make it more visually comprehensive, as well, save the end user of the library from routine.

Improving library classes

In order to make it possible to process different indicators with the same method, in the list of line names of each individual indicator we need to make it so that numerical values of lines of different indicators match. After all, each line of any indicator may be assigned to three types

Upper line, also known as the main one, also known as Jaws,
Lower line, also known as signal one, also known as Teeth and +DI,
Average line, also known as Lips and -DI

Ichimoku indicator lines are not considered here yet, but this will be at a later phase when it will be made multi-period, also.

And if, in such a manner all the lines correspond to each other we will easily make handlers of each indicator line in the same method, instead of making them differently.

Open \MQL5\Include\DoEasy\Defines.mqh and make the necessary changes to enlistment of types of standard indicator lines:

//+------------------------------------------------------------------+
//| Indicator lines                                                  |
//+------------------------------------------------------------------+
enum ENUM_INDICATOR_LINE_MODE
  {
   INDICATOR_LINE_MODE_MAIN      =  0,                      // Main line
   INDICATOR_LINE_MODE_SIGNAL    =  1,                      // Signal line
   INDICATOR_LINE_MODE_UPPER     =  0,                      // Upper line
   INDICATOR_LINE_MODE_LOWER     =  1,                      // Lower line
   INDICATOR_LINE_MODE_MIDDLE    =  2,                      // Middle line
   INDICATOR_LINE_MODE_JAWS      =  0,                      // Jaws line
   INDICATOR_LINE_MODE_TEETH     =  1,                      // Teeth line
   INDICATOR_LINE_MODE_LIPS      =  2,                      // Lips line
   INDICATOR_LINE_MODE_DI_PLUS   =  1,                      // Line +DI
   INDICATOR_LINE_MODE_DI_MINUS  =  2,                      // Line -DI
  };
//+------------------------------------------------------------------+

Since we need to copy data from standard indicator source array to calculated buffer object recipient array with a shift set for the indicator line, in \MQL5\Include\DoEasy\Objects\Indicators\Buffer.mqh of abstract buffer object class change a method which sets a shift of indicator graphical construction - now it has a check that it is a calculated buffer; and in this case return from the method occurs - the value is not set. Simply remove the check from the method:

//+------------------------------------------------------------------+
//| Set the indicator graphical construction shift                   |
//+------------------------------------------------------------------+
void CBuffer::SetShift(const int shift)
  {
   if(this.TypeBuffer()==BUFFER_TYPE_CALCULATE)
      return;
   this.SetProperty(BUFFER_PROP_SHIFT,shift);
   ::PlotIndexSetInteger((int)this.GetProperty(BUFFER_PROP_INDEX_PLOT),PLOT_SHIFT,shift);
  }
//+------------------------------------------------------------------+

Now, the method looks as follows:

//+------------------------------------------------------------------+
//| Set the indicator graphical construction shift                   |
//+------------------------------------------------------------------+
void CBuffer::SetShift(const int shift)
  {
   this.SetProperty(BUFFER_PROP_SHIFT,shift);
   if(this.TypeBuffer()!=BUFFER_TYPE_CALCULATE)
      ::PlotIndexSetInteger((int)this.GetProperty(BUFFER_PROP_INDEX_PLOT),PLOT_SHIFT,shift);
  }
//+------------------------------------------------------------------+

First, set shift value for any buffer, then if the buffer is not a calculated one set for it a shift of the line to be drawn.

In \MQL5\Include\DoEasy\Objects\Indicators\BufferCalculate.mqh of calculated buffer object we need to set the initial reference point (bar) from which data copying from standard indicator buffer starts. To do this, in data copying method of the specified indicator to buffer object array simply specify the value for data copying start with negative sign:

//+------------------------------------------------------------------+
//| It copies data of the specified indicator to buffer object array |
//+------------------------------------------------------------------+
int CBufferCalculate::FillAsSeries(const int indicator_handle,const int buffer_num,const int start_pos,const int count)
  {
   return ::CopyBuffer(indicator_handle,buffer_num,-start_pos,count,this.DataBuffer[0].Array);
  }
//+------------------------------------------------------------------+

Here all is simple: to the method as the initial bar for data copying the value of indicator line shift will be passed. If the shift is positive data will be copied with a negative shift, if the shift is negative data will be copied with a positive shift. Thus, we will always reach the correct start point of required data of source array.

Now, in \MQL5\Include\DoEasy\Collections\BuffersCollection.mqh of buffer objects collection class, improve all the methods for creation of standard indicators in which a shift of indicator lines is possible.

Let's use the method of creation of object of Alligator standard indicator as an example:

//+------------------------------------------------------------------+
//| Create multi-symbol multi-period Alligator                       |
//+------------------------------------------------------------------+
int CBuffersCollection::CreateAlligator(const string symbol,const ENUM_TIMEFRAMES timeframe,
                                        const int jaw_period,
                                        const int jaw_shift,
                                        const int teeth_period,
                                        const int teeth_shift,
                                        const int lips_period,
                                        const int lips_shift,
                                        const ENUM_MA_METHOD ma_method,
                                        const ENUM_APPLIED_PRICE applied_price,
                                        const int id=WRONG_VALUE)
  {
//--- Calculate and set the number of bars of line shift
   int num_bars=::PeriodSeconds(timeframe)/::PeriodSeconds(PERIOD_CURRENT);
   int shift_jaw=jaw_shift*num_bars;
   int shift_teeth=teeth_shift*num_bars;
   int shift_lips=lips_shift*num_bars;
//--- Create indicator handle and set default indicator
   int handle=::iAlligator(symbol,timeframe,jaw_period,shift_jaw,teeth_period,shift_teeth,lips_period,shift_lips,ma_method,applied_price);
   int identifier=(id==WRONG_VALUE ? IND_ALLIGATOR : id);
   color array_colors[1]={clrBlue};
   CBuffer *buff=NULL;
   if(handle!=INVALID_HANDLE)
     {
      //--- Create line buffer
      this.CreateLine();
      //--- Get the last created buffer object (drawn) and set to it all the necessary parameters of Jaws
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_jaw);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetShowData(true);
      buff.SetLineMode(INDICATOR_LINE_MODE_JAWS);
      buff.SetIndicatorName("Alligator");
      buff.SetIndicatorShortName("Alligator("+symbol+","+TimeframeDescription(timeframe)+": "+(string)jaw_period+","+(string)teeth_period+","+(string)lips_period+")");
      buff.SetLabel("Jaws("+symbol+","+TimeframeDescription(timeframe)+": "+(string)jaw_period+")");
      buff.SetColors(array_colors);
      
      //--- Create line buffer
      this.CreateLine();
      //--- Get the last created buffer object (drawn) and set to it all the necessary parameters of Teeth
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_teeth);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetShowData(true);
      buff.SetLineMode(INDICATOR_LINE_MODE_TEETH);
      buff.SetIndicatorName("Alligator");
      buff.SetIndicatorShortName("Alligator("+symbol+","+TimeframeDescription(timeframe)+": "+(string)jaw_period+","+(string)teeth_period+","+(string)lips_period+")");
      buff.SetLabel("Teeth("+symbol+","+TimeframeDescription(timeframe)+": "+(string)teeth_period+")");
      array_colors[0]=clrRed;
      buff.SetColors(array_colors);
      
      //--- Create line buffer
      this.CreateLine();
      //--- Get the last created buffer object (drawn) and set to it all the necessary parameters of Lips
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_lips);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetShowData(true);
      buff.SetLineMode(INDICATOR_LINE_MODE_LIPS);
      buff.SetIndicatorName("Alligator");
      buff.SetIndicatorShortName("Alligator("+symbol+","+TimeframeDescription(timeframe)+": "+(string)jaw_period+","+(string)teeth_period+","+(string)lips_period+")");
      buff.SetLabel("Lips("+symbol+","+TimeframeDescription(timeframe)+": "+(string)lips_period+")");
      array_colors[0]=clrLime;
      buff.SetColors(array_colors);
      
      //--- Create calculated buffer of Jaws in which standard indicator data will be stored
      this.CreateCalculate();
      //--- Get the last created buffer object (calculated) and set to it all the necessary parameters of Jaws
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_jaw);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetEmptyValue(EMPTY_VALUE);
      buff.SetLineMode(INDICATOR_LINE_MODE_JAWS);
      buff.SetIndicatorName("Alligator");
      buff.SetLabel("Jaws("+symbol+","+TimeframeDescription(timeframe)+": "+(string)jaw_period+")");
      
      //--- Create calculated buffer of Teeth in which standard indicator data will be stored
      this.CreateCalculate();
      //--- Get the last created buffer object (calculated) and set to it all the necessary parameters of Teeth
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_teeth);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetEmptyValue(EMPTY_VALUE);
      buff.SetLineMode(INDICATOR_LINE_MODE_TEETH);
      buff.SetIndicatorName("Alligator");
      buff.SetLabel("Teeth("+symbol+","+TimeframeDescription(timeframe)+": "+(string)teeth_period+")");
      
      //--- Create calculated buffer of Lips in which standard indicator data will be stored
      this.CreateCalculate();
      //--- Get the last created buffer object (calculated) and set to it all the necessary parameters of Lips
      buff=this.GetLastCreateBuffer();
      if(buff==NULL)
         return INVALID_HANDLE;
      buff.SetSymbol(symbol);
      buff.SetTimeframe(timeframe);
      buff.SetShift(shift_lips);
      buff.SetID(identifier);
      buff.SetIndicatorHandle(handle);
      buff.SetIndicatorType(IND_ALLIGATOR);
      buff.SetEmptyValue(EMPTY_VALUE);
      buff.SetLineMode(INDICATOR_LINE_MODE_LIPS);
      buff.SetIndicatorName("Alligator");
      buff.SetLabel("Lips("+symbol+","+TimeframeDescription(timeframe)+": "+(string)lips_period+")");
     }
   return handle;
  }
//+------------------------------------------------------------------+

Let’s analyze what we have here.

First, calculate how many bars of the current chart are contained in the chart period on which the indicator is calculated.
And further, calculate the number of shift bars by multiplying (passed to the method) shift values of three lines of the indicator by calculated number of bars.
In case of creation of indicator handle as parameters specifying the number of shift bars of each line specify above calculated values instead of those which were passed to the method.
To created buffer objects (both to drawn and calculated ones) set shift values calculated in the very beginning — for each couple of buffers (drawn-calculated) set values to a relevant indicator line (Jaws, Teeth and Lips).
Thus, the object of standard indicator and of its buffers is fully prepared to drawing the data with indicator line shift.
The remaining actions which are set in the method of creation of the object of Alligator standard indicator were considered in previous articles when methods of creation of objects of other standard indicators were described.

The above described changes and additions for calculation of indicator lines shift are already written to all the methods of creation of standard indicators which have the parameter determining the number of bars of line shift:
CreateAlligator(), CreateAMA(), CreateBands(), CreateDEMA(), CreateEnvelopes(), CreateFrAMA(), CreateMA(), CreateStdDev(), CreateTEMA() and CreateVIDYA().

Changes in each method are practically identical to those considered above and we will not discuss them here.
You can find the full code of buffer objects collection class in the attachments hereto.

In a situation where several standard indicator buffer objects are created but not all of them are used at the same time, the chart will display artefacts from currently unused buffer indicators. To avoid this, first fill in all the indicator buffer arrays with their empty value and, after that calculate those which must be calculated at the moment. To do this, create a method clearing all the buffers of their available standard indicator buffer objects by the specified timeseries index.

Declare the method in the public section of the class:

//--- Clears data of the buffer of (1) the specified standard indicator, (2) all the created standard indicators by the timeseries index
   void                    ClearDataBufferStdInd(const ENUM_INDICATOR std_ind,const int id,const int series_index);
   void                    ClearDataAllBuffersStdInd(int series_index);
//--- Set values for the current chart to buffers of the specified standard indicator by the timeseries index in accordance with buffer object symbol/period

Write its implementation outside the class body:

//+------------------------------------------------------------------+
//| Clear calculated buffer data for all the created                 |
//| standard indicators  by the timeseries index                     |
//+------------------------------------------------------------------+
void CBuffersCollection::ClearDataAllBuffersStdInd(int series_index)
  {
   CArrayObj *list=this.GetListBuffersWithID();
   if(list==NULL || list.Total()==0)
     {
      ::Print(DFUN_ERR_LINE,CMessage::Text(MSG_LIB_TEXT_BUFFER_TEXT_NO_BUFFER_OBJ));
      return;
     }
   int total=list.Total();
   for(int i=0;i<total;i++)
     {
      CBuffer *buff=list.At(i);
      if(buff==NULL || buff.TypeBuffer()==BUFFER_TYPE_CALCULATE || buff.IndicatorType()==WRONG_VALUE)
         continue;
      this.ClearDataBufferStdInd(buff.IndicatorType(),buff.ID(),series_index);
     }
  }
//+------------------------------------------------------------------+

Here:
Get the list of all the buffer objects to which indicator ID is specified.
In the loop by the whole obtained list get the next buffer object.
If for some reason the object is not got or it is a calculated buffer or a standard indicator type is not set for it (because any buffer object may have ID, not only a standard indicator) skip such object.
Finally, call buffer clearing method of the specified standard indicator considered in the previous article.

Improve methods for preparation and clearing of calculated buffer arrays which store data of standard indicator buffers. Earlier, in these methods we created code blocks which group single type actions for the indicators which names/assignments of their lines were identical. Now, when we assigned identical numeric values to all same-type lines (we discussed it in the very beginning of the story) in enlistment of types of standard indicator lines such methods may be simplified by bringing everything to three code blocks - for one, two and three lines of standard indicators.

A method which prepares calculated buffer data of the specified standard indicator:

//+------------------------------------------------------------------+
//| Prepare calculated buffer data                                   |
//| of the specified standard indicator                              |
//+------------------------------------------------------------------+
int CBuffersCollection::PreparingDataBufferStdInd(const ENUM_INDICATOR std_ind,const int id,const int total_copy)
  {
   CArrayObj *list_ind=this.GetListBufferByTypeID(std_ind,id);
   CArrayObj *list0=NULL,*list1=NULL,*list2=NULL;
   list_ind=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_TYPE,BUFFER_TYPE_CALCULATE,EQUAL);
   if(list_ind==NULL || list_ind.Total()==0)
     {
      ::Print(DFUN_ERR_LINE,CMessage::Text(MSG_LIB_TEXT_BUFFER_TEXT_NO_BUFFER_OBJ));
      return 0;
     }
   CBufferCalculate *buffer=NULL;
   int copied=WRONG_VALUE;
   int idx0=0,idx1=1,idx2=2;
   switch((int)std_ind)
     {
   //--- Single-buffer standard indicators
      case IND_AC          :
      case IND_AD          :
      case IND_AMA         :
      case IND_AO          :
      case IND_ATR         :
      case IND_BEARS       :
      case IND_BULLS       :
      case IND_BWMFI       :
      case IND_CCI         :
      case IND_CHAIKIN     :
      case IND_DEMA        :
      case IND_DEMARKER    :
      case IND_FORCE       :
      case IND_FRAMA       :
      case IND_MA          :
      case IND_MFI         :
      case IND_MOMENTUM    :
      case IND_OBV         :
      case IND_OSMA        :
      case IND_RSI         :
      case IND_SAR         :
      case IND_STDDEV      :
      case IND_TEMA        :
      case IND_TRIX        :
      case IND_VIDYA       :
      case IND_VOLUMES     :
      case IND_WPR         :
      
        buffer=list_ind.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),0,buffer.Shift(),total_copy);
        return copied;
      
   //--- Multi-buffer standard indicators
      case IND_ENVELOPES   :
      case IND_FRACTALS    :
      case IND_MACD        :
      case IND_RVI         :
      case IND_STOCHASTIC  :
        idx0=0;
        idx1=1;
        list0=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer=list0.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),idx0,buffer.Shift(),total_copy);
        if(copied<total_copy) return 0;
        
        list1=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer=list1.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),idx1,buffer.Shift(),total_copy);
        if(copied<total_copy) return 0;
        return copied;
      
      case IND_ALLIGATOR   :
      case IND_ADX         :
      case IND_ADXW        :
      case IND_BANDS       :
        if(std_ind==IND_BANDS)
          {
           idx0=1;
           idx1=2;
           idx2=0;
          }
        else
          {
           idx0=0;
           idx1=1;
           idx2=2;
          }
        list0=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer=list0.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),idx0,buffer.Shift(),total_copy);
        if(copied<total_copy) return 0;
        
        list1=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer=list1.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),idx1,buffer.Shift(),total_copy);
        if(copied<total_copy) return 0;
        
        list2=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,2,EQUAL);
        buffer=list2.At(0);
        if(buffer==NULL) return 0;
        copied=buffer.FillAsSeries(buffer.IndicatorHandle(),idx2,buffer.Shift(),total_copy);
        if(copied<total_copy) return 0;
        return copied;
      
      case IND_GATOR       :
      case IND_ICHIMOKU    :
        break;
      
      default:
        break;
     }
   return 0;
  }
//+------------------------------------------------------------------+

In the code block for three buffers of the indicator we added checking for Bollinger Bands indicator line processing because indexing of its buffers arrays differs from buffer indexing of all the remaining three-buffer standard indicators. Yet, processing of Gator Oscillator and Ichimoku Kinko Hyo indicators is unavailable for the reasons described in the beginning of the article.

A method which clears buffer data of the specified standard indicator by the timeseries index:

//+------------------------------------------------------------------+
//| Clear buffer data of the specified standard indicator            |
//| by the timeseries index                                          |
//+------------------------------------------------------------------+
void CBuffersCollection::ClearDataBufferStdInd(const ENUM_INDICATOR std_ind,const int id,const int series_index)
  {
//--- Get the list of buffer objects by type and ID
   CArrayObj *list_ind=this.GetListBufferByTypeID(std_ind,id);
   CArrayObj *list0=NULL,*list1=NULL,*list2=NULL;
   if(list_ind==NULL || list_ind.Total()==0)
      return;
   list_ind=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_TYPE,BUFFER_TYPE_DATA,EQUAL);
   if(list_ind.Total()==0)
      return;
   CBuffer *buffer=NULL;
   switch((int)std_ind)
     {
   //--- Single-buffer standard indicators
      case IND_AC          :
      case IND_AD          :
      case IND_AMA         :
      case IND_AO          :
      case IND_ATR         :
      case IND_BEARS       :
      case IND_BULLS       :
      case IND_BWMFI       :
      case IND_CCI         :
      case IND_CHAIKIN     :
      case IND_DEMA        :
      case IND_DEMARKER    :
      case IND_FORCE       :
      case IND_FRAMA       :
      case IND_MA          :
      case IND_MFI         :
      case IND_MOMENTUM    :
      case IND_OBV         :
      case IND_OSMA        :
      case IND_RSI         :
      case IND_SAR         :
      case IND_STDDEV      :
      case IND_TEMA        :
      case IND_TRIX        :
      case IND_VIDYA       :
      case IND_VOLUMES     :
      case IND_WPR         :
        buffer=list_ind.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        break;
      
   //--- Multi-buffer standard indicators
      case IND_ENVELOPES   :
      case IND_FRACTALS    :
      case IND_MACD        :
      case IND_RVI         :
      case IND_STOCHASTIC  :
      case IND_GATOR       :
        list0=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer=list0.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        
        list1=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer=list1.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        break;

      case IND_ALLIGATOR   :
      case IND_ADX         :
      case IND_ADXW        :
      case IND_BANDS       :
        list0=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer=list0.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        
        list1=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer=list1.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        
        list2=CSelect::ByBufferProperty(list_ind,BUFFER_PROP_IND_LINE_MODE,2,EQUAL);
        buffer=list2.At(0);
        if(buffer==NULL) return;
        buffer.SetBufferValue(0,series_index,buffer.EmptyValue());
        break;
      
      case IND_ICHIMOKU :
        break;
      
      default:
        break;
     }
  }
//+------------------------------------------------------------------+

All the standard indicators are distributed here in the same way by relevant code blocks - single-, two- and three-buffer standard indicators. Here, it is not important in which sequence buffer data will be cleared, therefore Bollinger Bands and Gator Oscillator are already included into code blocks of two- and three-buffer standard indicators processing. We do not process Ichimoku for now.

And since we combine processing of single-, two- and three-buffer standard indicators together now, we can considerably cut the code of the method setting values for the current chart to buffers of the specified standard indicator by the timeseries index in accordance with buffer object symbol/period. Here is the complete method code prior to its revision:

//+------------------------------------------------------------------+
//| Sets values for the current chart to buffers of the specified    |
//| standard indicator by the timeseries index in accordance         |
//| with buffer object symbol/period                                 |
//+------------------------------------------------------------------+
bool CBuffersCollection::SetDataBufferStdInd(const ENUM_INDICATOR ind_type,const int id,const int series_index,const datetime series_time,const char color_index=WRONG_VALUE)
  {
//--- Get the list of buffer objects by type and ID
   CArrayObj *list=this.GetListBufferByTypeID(ind_type,id);
   if(list==NULL || list.Total()==0)
     {
      ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_BUFFER_TEXT_NO_BUFFER_OBJ));
      return false;
     }
//--- Get the list of drawn buffers with ID
   CArrayObj *list_data=CSelect::ByBufferProperty(list,BUFFER_PROP_TYPE,BUFFER_TYPE_DATA,EQUAL);
   list_data=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_TYPE,ind_type,EQUAL);
//--- Get the list of calculated buffers with ID
   CArrayObj *list_calc=CSelect::ByBufferProperty(list,BUFFER_PROP_TYPE,BUFFER_TYPE_CALCULATE,EQUAL);
   list_calc=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_TYPE,ind_type,EQUAL);
//--- Leave if any of the lists is empty
   if(list_data.Total()==0 || list_calc.Total()==0)
      return false;
//--- Declare necessary objects and variables
   CBuffer *buffer_data0=NULL;
   CBuffer *buffer_data1=NULL;
   CBuffer *buffer_data2=NULL;
   CBuffer *buffer_calc0=NULL;
   CBuffer *buffer_calc1=NULL;
   CBuffer *buffer_calc2=NULL;
   int index_period=0;
   int series_index_start=0;
   int num_bars=1,index=0;
   uchar clr=color_index;
   long vol0=0,vol1=0;
   datetime time_period=0,time_shift=0;
   double value00=EMPTY_VALUE, value01=EMPTY_VALUE;
   double value10=EMPTY_VALUE, value11=EMPTY_VALUE;
   double value20=EMPTY_VALUE, value21=EMPTY_VALUE;

//--- Depending on standard indicator type
   switch((int)ind_type)
     {
   //--- Single-buffer standard indicators
      case IND_AC       :
      case IND_AD       :
      case IND_AMA      :
      case IND_AO       :
      case IND_ATR      :
      case IND_BEARS    :
      case IND_BULLS    :
      case IND_BWMFI    :
      case IND_CCI      :
      case IND_CHAIKIN  :
      case IND_DEMA     :
      case IND_DEMARKER :
      case IND_FORCE    :
      case IND_FRAMA    :
      case IND_MA       :
      case IND_MFI      :
      case IND_MOMENTUM :
      case IND_OBV      :
      case IND_OSMA     :
      case IND_RSI      :
      case IND_SAR      :
      case IND_STDDEV   :
      case IND_TEMA     :
      case IND_TRIX     :
      case IND_VIDYA    :
      case IND_VOLUMES  :
      case IND_WPR      :
        //--- Get objects of drawn and calculated buffers
        buffer_data0=list_data.At(0);
        buffer_calc0=list_calc.At(0);
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period of indicator buffer chart which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Calculate bar shift depending on a direction of indicator line shift
           //index_period+=buffer_data0.Shift();
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period); // -buffer_calc0.Shift()+index_shift
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars+(num_bars*buffer_calc0.Shift())));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           if(ind_type!=IND_BWMFI)
              clr=(color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           else
             {
              vol0=::iVolume(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
              vol1=::iVolume(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period+1);
              clr=
                (
                 value00>value01 && vol0>vol1 ? 0 :
                 value00<value01 && vol0<vol1 ? 1 :
                 value00>value01 && vol0<vol1 ? 2 :
                 value00<value01 && vol0>vol1 ? 3 : 4
                );
             }
           buffer_data0.SetBufferColorIndex(index,clr);
          }
        return true;
      
   //--- Multi-buffer standard indicators
      case IND_ADX   :
      case IND_ADXW  :
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MAIN,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_DI_PLUS,EQUAL);
        buffer_data1=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_DI_MINUS,EQUAL);
        buffer_data2=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MAIN,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_DI_PLUS,EQUAL);
        buffer_calc1=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_DI_MINUS,EQUAL);
        buffer_calc2=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        if(buffer_calc2==NULL || buffer_data2==NULL || buffer_calc2.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        value20=buffer_calc2.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        value21=(series_index_start+num_bars>buffer_data2.GetDataTotal()-1 ? value20 : buffer_data2.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data2.SetBufferValue(2,index,value20);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
           buffer_data2.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value20>value21 ? 0 : value20<value21 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_BANDS    :
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_data1=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MIDDLE,EQUAL);
        buffer_data2=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_calc1=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MIDDLE,EQUAL);
        buffer_calc2=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        if(buffer_calc2==NULL || buffer_data2==NULL || buffer_calc2.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        value20=buffer_calc2.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        value21=(series_index_start+num_bars>buffer_data2.GetDataTotal()-1 ? value20 : buffer_data2.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(0,index,value10);
           buffer_data2.SetBufferValue(0,index,value20);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
           buffer_data2.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value20>value21 ? 0 : value20<value21 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_ENVELOPES :
      case IND_FRACTALS  :
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_data1=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_calc1=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_MACD        :
      case IND_RVI         :
      case IND_STOCHASTIC  :
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MAIN,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_SIGNAL,EQUAL);
        buffer_data1=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_MAIN,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_SIGNAL,EQUAL);
        buffer_calc1=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_ALLIGATOR:
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_JAWS,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_TEETH,EQUAL);
        buffer_data1=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LIPS,EQUAL);
        buffer_data2=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_JAWS,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_TEETH,EQUAL);
        buffer_calc1=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LIPS,EQUAL);
        buffer_calc2=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        if(buffer_calc2==NULL || buffer_data2==NULL || buffer_calc2.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        value20=buffer_calc2.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        value21=(series_index_start+num_bars>buffer_data2.GetDataTotal()-1 ? value20 : buffer_data2.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(0,index,value10);
           buffer_data2.SetBufferValue(0,index,value20);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
           buffer_data2.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value20>value21 ? 0 : value20<value21 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_GATOR    :
        //--- Get objects of drawn and calculated buffers
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_data1=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_UPPER,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,INDICATOR_LINE_MODE_LOWER,EQUAL);
        buffer_calc1=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        //--- Find bar index on a period which corresponds to the time of current bar beginning
        index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
        if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
           return false;
        //--- Get the value by this index from indicator buffer
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
        if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
          {
           series_index_start=series_index;
           num_bars=1;
          }
        else
          {
           //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
           time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
           if(time_period==0) return false;
           //--- Get the current chart bar which corresponds to the time
           series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
           if(series_index_start==WRONG_VALUE) return false;
           //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
           num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
           if(num_bars==0) num_bars=1;
          }
        //--- Take values for color calculation
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10<value11 ? 0 : value10>value11 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_ICHIMOKU :
        break;
      
      default:
        break;
     }
   return false;
  }
//+------------------------------------------------------------------+

Identical code blocks are highlighted in color in method listing. It is obvious that we can put all this similar processing into a single method which will allow for reducing method code.

In the public section of the class declare the private method preparing data of the specified standard indicator for setting values on the current symbol chart (to this method move all the similar processing from the above considered method from the previous article):

//--- Clear buffer data of (1) the specified standard indicator, (2) all the created standard indicators by the timeseries index
   void                    ClearDataBufferStdInd(const ENUM_INDICATOR std_ind,const int id,const int series_index);
   void                    ClearDataAllBuffersStdInd(int series_index);
//--- Set values for the current chart to buffers of the specified standard indicator by the timeseries index in accordance with buffer object symbol/period
   bool                    SetDataBufferStdInd(const ENUM_INDICATOR std_ind,const int id,const int series_index,const datetime series_time,const char color_index=WRONG_VALUE);
private:
//--- Prepare data of the specified standard indicator for setting values on the current symbol chart
   int                     PreparingSetDataStdInd(CBuffer *buffer_data0,CBuffer *buffer_data1,CBuffer *buffer_data2,
                                                  CBuffer *buffer_calc0,CBuffer *buffer_calc1,CBuffer *buffer_calc2,
                                                  const ENUM_INDICATOR ind_type,
                                                  const int series_index,
                                                  const datetime series_time,
                                                  int &index_period,
                                                  int &num_bars,
                                                  double &value00,
                                                  double &value01,
                                                  double &value10,
                                                  double &value11,
                                                  double &value20,
                                                  double &value21);
public:

//--- Return the buffer (1) by the graphical series name, (2) timeframe,
//--- (3) Plot index, (4) object index in the collection list, (5) the last created,
//--- buffer list (6) by ID, (7) standard indicator type, (8) type and ID

To the method pass pointers to buffer objects and timeseries data, as well variables by the link which values will have to be returned from the method for their further processing in the method we reduce.

Implement the method outside the class body:

//+------------------------------------------------------------------+
//| Prepare data of the specified standard indicator                 |
//| for setting values on the current symbol chart                   |
//+------------------------------------------------------------------+
int CBuffersCollection::PreparingSetDataStdInd(CBuffer *buffer_data0,CBuffer *buffer_data1,CBuffer *buffer_data2,
                                               CBuffer *buffer_calc0,CBuffer *buffer_calc1,CBuffer *buffer_calc2,
                                               const ENUM_INDICATOR ind_type,
                                               const int series_index,
                                               const datetime series_time,
                                               int &index_period,
                                               int &num_bars,
                                               double &value00,
                                               double &value01,
                                               double &value10,
                                               double &value11,
                                               double &value20,
                                               double &value21)
  {
     //--- Find bar index on a period which corresponds to the time of current bar beginning
     index_period=::iBarShift(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),series_time,true);
     if(index_period==WRONG_VALUE || index_period>buffer_calc0.GetDataTotal()-1)
        return WRONG_VALUE;
     
     //--- Get the value by this index from indicator buffer
     if(buffer_calc0!=NULL)
        value00=buffer_calc0.GetDataBufferValue(0,index_period);
     if(buffer_calc1!=NULL)
        value10=buffer_calc1.GetDataBufferValue(0,index_period);
     if(buffer_calc2!=NULL)
        value20=buffer_calc2.GetDataBufferValue(0,index_period);
     
     int series_index_start=series_index;
     //--- For the current chart we don’t need to calculate a number of bars processed - only one bar is available
     if(buffer_calc0.Symbol()==::Symbol() && buffer_calc0.Timeframe()==::Period())
       {
        series_index_start=series_index;
        num_bars=1;
       }
     else
       {
        //--- Get the bar time which the bar with index_period index falls into on a period and symbol of calculated buffer
        datetime time_period=::iTime(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
        if(time_period==0) return false;
        //--- Get the current chart bar which corresponds to the time
        series_index_start=::iBarShift(::Symbol(),::Period(),time_period,true);
        if(series_index_start==WRONG_VALUE) return WRONG_VALUE;
        //--- Calculate the number of bars on the current chart which are to be filled in with calculated buffer data
        num_bars=::PeriodSeconds(buffer_calc0.Timeframe())/::PeriodSeconds(PERIOD_CURRENT);
        if(num_bars==0) num_bars=1;
       }
     //--- Take values for color calculation
     if(buffer_calc0!=NULL)
        value01=(series_index_start+num_bars>buffer_data0.GetDataTotal()-1 ? value00 : buffer_data0.GetDataBufferValue(0,series_index_start+num_bars));
     if(buffer_calc1!=NULL)
        value11=(series_index_start+num_bars>buffer_data1.GetDataTotal()-1 ? value10 : buffer_data1.GetDataBufferValue(0,series_index_start+num_bars));
     if(buffer_calc2!=NULL)
        value21=(series_index_start+num_bars>buffer_data2.GetDataTotal()-1 ? value20 : buffer_data2.GetDataBufferValue(0,series_index_start+num_bars));
   
   return series_index_start;
  }
//+------------------------------------------------------------------+

This is clear - we moved a repeated code block from one method to another, a new one. Since in the method reduced it is necessary to use multiple data which are calculated within this private method, simply pass variables to the new method by the link and all the changes in values of those variables will be available in the calling method. Apart from setting values to variables by the link this method returns the bar index from which, in a loop it is necessary to fill in buffer data on the current chart in the calling method. In case of data processing failure the method returns the value of -1.

Now, let’s see how much we reduced the method which sets values for the current chart to buffers of the specified standard indicator by the timeseries index in accordance with buffer object symbol/period:

//+------------------------------------------------------------------+
//| Sets values for the current chart to buffers of the specified    |
//| standard indicator by the timeseries index in accordance         |
//| with buffer object symbol/period                                 |
//+------------------------------------------------------------------+
bool CBuffersCollection::SetDataBufferStdInd(const ENUM_INDICATOR ind_type,const int id,const int series_index,const datetime series_time,const char color_index=WRONG_VALUE)
  {
//--- Get the list of buffer objects by type and ID
   CArrayObj *list=this.GetListBufferByTypeID(ind_type,id);
   if(list==NULL || list.Total()==0)
     {
      ::Print(DFUN,CMessage::Text(MSG_LIB_TEXT_BUFFER_TEXT_NO_BUFFER_OBJ));
      return false;
     }
//--- Get the list of drawn buffers with ID
   CArrayObj *list_data=CSelect::ByBufferProperty(list,BUFFER_PROP_TYPE,BUFFER_TYPE_DATA,EQUAL);
   list_data=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_TYPE,ind_type,EQUAL);
//--- Get the list of calculated buffers with ID
   CArrayObj *list_calc=CSelect::ByBufferProperty(list,BUFFER_PROP_TYPE,BUFFER_TYPE_CALCULATE,EQUAL);
   list_calc=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_TYPE,ind_type,EQUAL);
//--- Leave if any of the lists is empty
   if(list_data.Total()==0 || list_calc.Total()==0)
      return false;
  
//--- Declare necessary objects and variables
   CBuffer *buffer_data0=NULL;
   CBuffer *buffer_data1=NULL;
   CBuffer *buffer_data2=NULL;
   CBuffer *buffer_calc0=NULL;
   CBuffer *buffer_calc1=NULL;
   CBuffer *buffer_calc2=NULL;
   double value00=EMPTY_VALUE, value01=EMPTY_VALUE;
   double value10=EMPTY_VALUE, value11=EMPTY_VALUE;
   double value20=EMPTY_VALUE, value21=EMPTY_VALUE;
   long vol0=0,vol1=0;
   int series_index_start=series_index,index_period=0, index=0,num_bars=1;
   uchar clr=0;
//--- Depending on standard indicator type

   switch((int)ind_type)
     {
   //--- Single-buffer standard indicators
      case IND_AC       :
      case IND_AD       :
      case IND_AMA      :
      case IND_AO       :
      case IND_ATR      :
      case IND_BEARS    :
      case IND_BULLS    :
      case IND_BWMFI    :
      case IND_CCI      :
      case IND_CHAIKIN  :
      case IND_DEMA     :
      case IND_DEMARKER :
      case IND_FORCE    :
      case IND_FRAMA    :
      case IND_MA       :
      case IND_MFI      :
      case IND_MOMENTUM :
      case IND_OBV      :
      case IND_OSMA     :
      case IND_RSI      :
      case IND_SAR      :
      case IND_STDDEV   :
      case IND_TEMA     :
      case IND_TRIX     :
      case IND_VIDYA    :
      case IND_VOLUMES  :
      case IND_WPR      :
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_calc0=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        
        series_index_start=PreparingSetDataStdInd(buffer_data0,buffer_data1,buffer_data2,buffer_calc0,buffer_calc1,buffer_calc2,
                                                  ind_type,series_index,series_time,index_period,num_bars,value00,value01,value10,value11,value20,value21);
        if(series_index_start==WRONG_VALUE)
           return false;
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           if(ind_type!=IND_BWMFI)
              clr=(color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           else
             {
              vol0=::iVolume(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period);
              vol1=::iVolume(buffer_calc0.Symbol(),buffer_calc0.Timeframe(),index_period+1);
              clr=
                (
                 value00>value01 && vol0>vol1 ? 0 :
                 value00<value01 && vol0<vol1 ? 1 :
                 value00>value01 && vol0<vol1 ? 2 :
                 value00<value01 && vol0>vol1 ? 3 : 4
                );
             }
           buffer_data0.SetBufferColorIndex(index,clr);
          }
        return true;
      
   //--- Multi-buffer standard indicators
      case IND_ENVELOPES :
      case IND_FRACTALS  :
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer_data1=list.At(0);
           
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer_calc1=list.At(0);
           
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        
        series_index_start=PreparingSetDataStdInd(buffer_data0,buffer_data1,buffer_data2,buffer_calc0,buffer_calc1,buffer_calc2,
                                                  ind_type,series_index,series_time,index_period,num_bars,value00,value01,value10,value11,value20,value21);
        if(series_index_start==WRONG_VALUE)
           return false;
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_ADX         :
      case IND_ADXW        :
      case IND_BANDS       :
      case IND_MACD        :
      case IND_RVI         :
      case IND_STOCHASTIC  :
      case IND_ALLIGATOR   :
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_data0=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer_data1=list.At(0);
        list=CSelect::ByBufferProperty(list_data,BUFFER_PROP_IND_LINE_MODE,2,EQUAL);
        buffer_data2=list.At(0);
        
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,0,EQUAL);
        buffer_calc0=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,1,EQUAL);
        buffer_calc1=list.At(0);
        list=CSelect::ByBufferProperty(list_calc,BUFFER_PROP_IND_LINE_MODE,2,EQUAL);
        buffer_calc2=list.At(0);
        
        if(buffer_calc0==NULL || buffer_data0==NULL || buffer_calc0.GetDataTotal(0)==0)
           return false;
        if(buffer_calc1==NULL || buffer_data1==NULL || buffer_calc1.GetDataTotal(0)==0)
           return false;
        if(buffer_calc2==NULL || buffer_data2==NULL || buffer_calc2.GetDataTotal(0)==0)
           return false;
        
        series_index_start=PreparingSetDataStdInd(buffer_data0,buffer_data1,buffer_data2,buffer_calc0,buffer_calc1,buffer_calc2,
                                                  ind_type,series_index,series_time,index_period,num_bars,value00,value01,value10,value11,value20,value21);
        if(series_index_start==WRONG_VALUE)
           return false;
        //--- In a loop, by the number of bars in  num_bars fill in the drawn buffer with a value from the calculated buffer taken by index_period index
        //--- and set the drawn buffer color depending on a proportion of value00 and value01 values
        for(int i=0;i<num_bars;i++)
          {
           index=series_index_start-i;
           buffer_data0.SetBufferValue(0,index,value00);
           buffer_data1.SetBufferValue(1,index,value10);
           buffer_data2.SetBufferValue(2,index,value20);
           buffer_data0.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value00>value01 ? 0 : value00<value01 ? 1 : 2) : color_index);
           buffer_data1.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value10>value11 ? 0 : value10<value11 ? 1 : 2) : color_index);
           buffer_data2.SetBufferColorIndex(index,color_index==WRONG_VALUE ? uchar(value20>value21 ? 0 : value20<value21 ? 1 : 2) : color_index);
          }
        return true;
      
      case IND_GATOR    :
      case IND_ICHIMOKU :
        break;
      
      default:
        break;
     }
   return false;
  }
//+------------------------------------------------------------------+

All the calculations repeating from one block to another are now replaced by the call of the method and check of the result returned from it. Also, here we don’t process Gator Oscillator and Ichimoku Kinko Hyo for the above specified reasons.

Test

To perform the test, let's take the test indicator from the previous article and save it in a new folder \MQL5\Indicators\TestDoEasy\Part50\ under a new name TestDoEasyPart50.mq5.

To external parameters of the indicator add indicator line shift:

//--- input variables
sinput   string               InpUsedSymbols    =  "GBPUSD";      // Used symbol (one only)
sinput   ENUM_TIMEFRAMES      InpPeriod         =  PERIOD_M30;    // Used chart period
sinput   ENUM_INDICATOR       InpIndType        =  IND_AC;        // Type standard indicator
sinput   int                  InpShift          =  0;             // Indicator line shift
//---
sinput   bool                 InpUseSounds      =  true;          // Use sounds
//--- indicator buffers

We need to check how indicator line shift works. Standard indicators having a feature of displaying a shift line, all display their data in chart’s main window (except for Gator Oscillator displayed in a subwindow but not implemented by us, yet). Therefore, in OnInit() handler add a code block for creating standard indicator objects working in the main window:

//--- indicator buffers mapping
//--- Create all the necessary buffer objects for constructing the selected standard indicator
   bool success=false;
   switch(InpIndType)
     {
//--- Single-buffer standard indicators in the main window
      case IND_AMA         :  success=engine.BufferCreateAMA(InpUsedSymbols,InpPeriod,9,2,30,InpShift,PRICE_CLOSE,1);                  break;
      case IND_DEMA        :  success=engine.BufferCreateDEMA(InpUsedSymbols,InpPeriod,14,InpShift,PRICE_CLOSE,1);                     break;
      case IND_FRAMA       :  success=engine.BufferCreateFrAMA(InpUsedSymbols,InpPeriod,14,InpShift,PRICE_CLOSE,1);                    break;
      case IND_MA          :  success=engine.BufferCreateMA(InpUsedSymbols,InpPeriod,10,InpShift,MODE_SMA,PRICE_CLOSE,1);              break;
      case IND_SAR         :  success=engine.BufferCreateSAR(InpUsedSymbols,InpPeriod,0.02,0.2,1);                                     break;
      case IND_TEMA        :  success=engine.BufferCreateTEMA(InpUsedSymbols,InpPeriod,14,InpShift,PRICE_CLOSE,1);                     break;
      case IND_VIDYA       :  success=engine.BufferCreateVIDYA(InpUsedSymbols,InpPeriod,9,12,InpShift,PRICE_CLOSE,1);                  break;
      
//--- Multi-buffer standard indicators in the main window
      case IND_ALLIGATOR   :  success=engine.BufferCreateAlligator(InpUsedSymbols,InpPeriod,13,8,8,5,5,3,MODE_SMMA,PRICE_MEDIAN,1);    break;
      case IND_BANDS       :  success=engine.BufferCreateBands(InpUsedSymbols,InpPeriod,20,InpShift,2.0,PRICE_CLOSE,1);                break;
      case IND_ENVELOPES   :  success=engine.BufferCreateEnvelopes(InpUsedSymbols,InpPeriod,14,InpShift,MODE_SMA,PRICE_CLOSE,0.1,1);   break;
      case IND_FRACTALS    :  success=engine.BufferCreateFractals(InpUsedSymbols,InpPeriod,1);                                         break;
      
      default:
        break;
     }
   if(!success)
     {
      Print(TextByLanguage("Error. Indicator not created"));
      return INIT_FAILED;
     }

Pass the external parameter which sets line shift to methods of creation of standard indicator objects. For Alligator indicator shifts are specified for each of its three lines and those values are already included into logic of indicator idea by its author.

In previous test indicators we had a code block assigning and setting levels for indicators in the subwindow and capacity of indicator data display in terminal data window:

//--- Set the levels where they are required and determine data capacity
   int digits=(int)SymbolInfoInteger(InpUsedSymbols,SYMBOL_DIGITS);
   switch(InpIndType)
     {
      case IND_AD          :
      case IND_CHAIKIN     :
      case IND_OBV         :
      case IND_VOLUMES     : digits=0;    break;
      
      case IND_AO          :
      case IND_BEARS       :
      case IND_BULLS       :
      case IND_FORCE       :
      case IND_STDDEV      :
      case IND_AMA         :
      case IND_DEMA        :
      case IND_FRAMA       :
      case IND_MA          :
      case IND_TEMA        :
      case IND_VIDYA       :
      case IND_BANDS       :
      case IND_ENVELOPES   :
      case IND_MACD        : digits+=1;   break;
      
      case IND_AC          :
      case IND_OSMA        : digits+=2;   break;
      
      case IND_MOMENTUM    : digits=2;    break;
      
      case IND_CCI         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,100);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,-100);
        digits=2;
        break;
      case IND_DEMARKER    :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,0.7);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,0.3);
        digits=3;
        break;
      case IND_MFI         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,20);
        break;
      case IND_RSI         :
        IndicatorSetInteger(INDICATOR_LEVELS,3);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,70);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,50);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,2,30);
        digits=2;
        break;
      case IND_STOCHASTIC  :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,20);
        digits=2;
        break;
      case IND_WPR         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,-80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,-20);
        digits=2;
        break;
     
      case IND_ATR         :              break;
      case IND_SAR         :              break;
      case IND_TRIX        :              break;
      
      default:
        IndicatorSetInteger(INDICATOR_LEVELS,0);
        break;
     }
//--- Set a short name for the indicator and data capacity
   string label=engine.BufferGetIndicatorShortNameByTypeID(InpIndType,1);
   IndicatorSetString(INDICATOR_SHORTNAME,label);
   IndicatorSetInteger(INDICATOR_DIGITS,digits);

Get rid of this code block in the final indicator. To do this in the file of service functions of the library \MQL5\Include\DoEasy\Services\DELib.mqh write a new function to which remove this code block:

//+------------------------------------------------------------------+
//| Set capacity and levels to standard indicator                    |
//+------------------------------------------------------------------+
void SetIndicatorLevels(const string symbol,const ENUM_INDICATOR ind_type)
  {
   int digits=(int)SymbolInfoInteger(symbol,SYMBOL_DIGITS);
   switch(ind_type)
     {
      case IND_AD          :
      case IND_CHAIKIN     :
      case IND_OBV         :
      case IND_VOLUMES     : digits=0;    break;
      
      case IND_AO          :
      case IND_BEARS       :
      case IND_BULLS       :
      case IND_FORCE       :
      case IND_STDDEV      :
      case IND_AMA         :
      case IND_DEMA        :
      case IND_FRAMA       :
      case IND_MA          :
      case IND_TEMA        :
      case IND_VIDYA       :
      case IND_BANDS       :
      case IND_ENVELOPES   :
      case IND_MACD        : digits+=1;   break;
      
      case IND_AC          :
      case IND_OSMA        : digits+=2;   break;
      
      case IND_MOMENTUM    : digits=2;    break;
      
      case IND_CCI         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,100);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,-100);
        digits=2;
        break;
      case IND_DEMARKER    :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,0.7);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,0.3);
        digits=3;
        break;
      case IND_MFI         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,20);
        break;
      case IND_RSI         :
        IndicatorSetInteger(INDICATOR_LEVELS,3);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,70);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,50);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,2,30);
        digits=2;
        break;
      case IND_STOCHASTIC  :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,20);
        digits=2;
        break;
      case IND_WPR         :
        IndicatorSetInteger(INDICATOR_LEVELS,2);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,0,-80);
        IndicatorSetDouble(INDICATOR_LEVELVALUE,1,-20);
        digits=2;
        break;
     
      case IND_ATR         :              break;
      case IND_SAR         :              break;
      case IND_TRIX        :              break;
      
      default:
        IndicatorSetInteger(INDICATOR_LEVELS,0);
        break;
     }
   IndicatorSetInteger(INDICATOR_DIGITS,digits);
  }
//+------------------------------------------------------------------+

Now, in OnInit() handler of the indicator, in its very end, it is enough to simply call this function which makes the code more simple and visually comprehensive:

//--- Set a short name for the indicator, data capacity and levels
   string label=engine.BufferGetIndicatorShortNameByTypeID(InpIndType,1);
   IndicatorSetString(INDICATOR_SHORTNAME,label);
   SetIndicatorLevels(InpUsedSymbols,InpIndType);

//--- Succeeded
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+

Leave OnCalculate() handler unchanged. Find the entire code of the test indicator in the files attached below.

Compile the indicator and launch it on EURUSD H1 chart having preliminary set the use of EURUSD H4 symbol in the settings. Set indicator line shift as 4 bars and select Bollinger Bands indicator. Then select Alligator indicator in the settings:

As we see, Bollinger Bands is correctly displayed with the specified shift of 4 bars and Alligator does not react to a 4 bar shift - it possesses set default values immediately when created in OnInit() code equal to those values in the standard indicator:

//--- Multi-buffer standard indicators in the main window
      case IND_ALLIGATOR   :  success=engine.BufferCreateAlligator(InpUsedSymbols,InpPeriod,13,8,8,5,5,3,MODE_SMMA,PRICE_MEDIAN,1);    break;

And Alligator also correctly displays its lines with the standard shift of its lines.

What's next?

In the next article we will continue developing library methods for working with standard indicators in multi-symbol multi-period mode.

All files of the current version of the library are attached below together with the test indicator file for you to test and download.
Leave your comments, questions and suggestions in the comments to the article.
Please keep in mind that here I have developed the MQL5 test indicator for MetaTrader 5.
The attached files are intended only for MetaTrader 5. The current library version has not been tested in MetaTrader 4.
After developing and testing the functionality for working with indicator buffers, I will try to implement some MQL5 features in MetaTrader 4.

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Translated from Russian by MetaQuotes Ltd.
Original article: https://www.mql5.com/ru/articles/8331

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Timeseries in DoEasy library (part 50): Multi-period multi-symbol standard indicators with a shift

Table of contents

Concept

Improving library classes

Test

What's next?

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