MQL5 Indicators

Seantjuh1991 2020.05.23 18:29

Hey guys,

I am reprogramming my MQL4 code to MQL5. I do have a question about the indicator change.

So in MQL4 it simply looks something like:

void OnTick()
{
double movingAverage = iMA(NULL,PERIOD_CURRENT,13,0,MODE_EMA,PRICE_CLOSE,0);
}

So the variable gets updated every tick.

But in MQL5 we have to I guess overcomplicate things.

//GLOBAL DATA
      
double moving_average;
double movingAverage[];


//+---------------------------------------------------------------------------------------------------------+
//|                                                INITIALIZATION                                           |
//+---------------------------------------------------------------------------------------------------------+
int OnInit()
  {
   moving_average = iMA(NULL,PERIOD_CURRENT,20,0,MODE_EMA,PRICE_CLOSE); 
   CopyBuffer(moving_average,0,0,100,movingAverage)
   ArraySetAsSeries(movingAverage,true);

  }

//We skip OnDeinit here

//+---------------------------------------------------------------------------------------------------------+
//|                                               EXECUTE ON TICK                                           |
//+---------------------------------------------------------------------------------------------------------+
void OnTick()
  {

   double LastMovingAverage = movingAverage[0];

So my question is does the moving average prices get updated like it does in my MQL 4 code? Or Do I have to shift things from OnInit to the OnTick function? Because OnInit only executes one time...

Would appreciate help with this!

Documentation on MQL5: Constants, Enumerations and Structures / Indicator Constants / Price Constants

www.mql5.com

Calculations of technical indicators require price values and/or values of volumes, on which calculations will be performed. There are 7 predefined identifiers from the ENUM_APPLIED_PRICE enumeration, used to specify the desired price base for calculations. If a technical indicator uses for calculations price data, type of which is set by...

Vladimir Karputov 2020.05.23 19:45 #1

Seantjuh1991 :

Hey guys,

I am reprogramming my MQL4 code to MQL5. I do have a question about the indicator change.

So in MQL4 it simply looks something like:

So the variable gets updated every tick.

But in MQL5 we have to I guess overcomplicate things.

In OnInit, you need to create an indicator handle.

In OnTick you need to use copying.

Creating an iMA indicator handle, getting indicator values

Forum on trading, automated trading systems and testing trading strategies

How to start with MQL5

Vladimir Karputov, 2020.03.08 09:04

Creating an iMA indicator handle, getting indicator values

(code: iMA Values on a Chart)

The main rule: the indicator handle needs to be received once (it is optimal to do this in the OnInit function).

Input parameters and the variable in which the indicator handle is stored:

//+------------------------------------------------------------------+
//|                                        iMA Values on a Chart.mq5 |
//|                              Copyright © 2019, Vladimir Karputov |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2019, Vladimir Karputov"
#property version   "1.00"
//--- input parameters
input int                  Inp_MA_ma_period     = 12;          // MA: averaging period
input int                  Inp_MA_ma_shift      = 5;           // MA: horizontal shift
input ENUM_MA_METHOD       Inp_MA_ma_method     = MODE_SMA;    // MA: smoothing type
input ENUM_APPLIED_PRICE   Inp_MA_applied_price = PRICE_CLOSE; // MA: type of price
//---
int    handle_iMA;                           // variable for storing the handle of the iMA indicator
//+------------------------------------------------------------------+
//| Expert initialization function                                   |

Creating a handle (checking the result)

//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//--- create handle of the indicator iMA
   handle_iMA=iMA(Symbol(),Period(),Inp_MA_ma_period,Inp_MA_ma_shift,
                  Inp_MA_ma_method,Inp_MA_applied_price);
//--- if the handle is not created
   if(handle_iMA==INVALID_HANDLE)
     {
      //--- tell about the failure and output the error code
      PrintFormat("Failed to create handle of the iMA indicator for the symbol %s/%s, error code %d",
                  Symbol(),
                  EnumToString(Period()),
                  GetLastError());
      //--- the indicator is stopped early
      return(INIT_FAILED);
     }
//---
   return(INIT_SUCCEEDED);
  }

Getting values (I use the iGetArray generic function). Please note: for the array "array_ma" I use "ArraySetAsSeries" - in this case, in the “array_ma” array, the element with the index “0” corresponds to the rightmost bar on the chart (bar # 0)

//+------------------------------------------------------------------+
//| Expert tick function                                             |
//+------------------------------------------------------------------+
void OnTick()
  {
//---
   double array_ma[];
   ArraySetAsSeries(array_ma,true);
   int start_pos=0,count=3;
   if(!iGetArray(handle_iMA,0,start_pos,count,array_ma))
      return;

   string text="";
   for(int i=0; i<count; i++)
      text=text+IntegerToString(i)+": "+DoubleToString(array_ma[i],Digits()+1)+"\n";
//---
   Comment(text);
  }