The class for drawing Moving Average using the ring buffer – indicator MetaTrader 5

Description

The CMAOnRingBuffer class is designed for calculation of Moving Averages (Moving Average) using the algorithm of the ring buffer. 

Declaration

class CMAOnRingBuffer :public CArrayRing

Title

#include <IncOnRingBuffer\CMAOnRingBuffer.mqh>

File of the CMAOnRingBuffer.mqh class should be placed in the IncOnRingBuffer folder that need to be established in MQL5\Include\. Two files with the examples used by the class from this folder are attached to the description. File with the class of the ring buffer also must be in this folder.

Class methods

//--- initialization method:
bool Init(                                // if error it returns false, if successful - true
   int            ma_period   = 14,       // period of Moving Average smoothing 
   ENUM_MA_METHOD ma_method   = MODE_SMA, // method of Moving Average smoothing
   int            size_buffer = 256,      // the ring buffer size, the number of stored data
   bool           as_series   = false     // true, if a time series, false if a usual indexing of the input data
   );             

//--- method of calculation based on a time series or indicator buffer:          
int MainOnArray(                  // returns the number of the processed elements of the array  
   const int     rates_total,     // size of array array[]
   const int     prev_calculated, // processed elements of the array in the previous call
   const double &array[]          // array for the calculation
   );

//--- method of calculation based on separate series elements of the array           
double MainOnValue(              // returns MA value for the set element
   const int    rates_total,     // the size of the array
   const int    prev_calculated, // processed elements in the array
   const int    begin,           // from where the significant data of the array starts
   const double value,           // the array element value 
   const int    index            // the array element index
   );

//--- methods of access to the data:
int    BarsRequired();   // Returns necessary number of bars to draw the indicator
string Name();           // Returns the indicator name
string MAMethod();       // Returns the method of smoothing in the form of the text line  
int    MAPeriod();       // Returns the period of smoothing

To get the calculated data of the indicator from the ring buffer is possible as from the usual array. For example:

#include <IncOnRingBuffer\CMAOnRingBuffer.mqh>
CMAOnRingBuffer ma;
...
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int OnCalculate(const int rates_total,
                const int prev_calculated,
                const int begin,
                const double &price[])
  {
//--- calculation of the indicator:
   ma.MainOnArray(rates_total,prev_calculated,price);

...
     
//--- copy data from the "ma" ring buffer to the indicator:  
   for(int i=start;i<rates_total;i++)
     {
      MA_Buffer[i]=ma[rates_total-1-i];
     }
   return(rates_total);
  }

Examples

1. The indicator calculates the Test_MA_OnArrayRB.mq5 file on the basis of the price time series. The MainOnArray() method application is demonstrated 
2. The Test_MA_OnValueRB.mq5 file demonstates use of the MainOnValue() method. At first the MA indicator is calculated and draws. Then on the basis of the ring buffer of this indicator, one more МА indicator is calculated. 

The result of the work of the Test_MA_OnArrayRB.mq5 with the size of the ring buffer of 256 elements

The result of the work of the Test_MA_OnValueRB.mq5 with the size of the ring buffer of 256 elements

When writing code the developments of MetaQuotes Software Corp., Integer and GODZILLA were used.