Questions from Beginners MQL5 MT5 MetaTrader 5 - page 1467

 
Valeriy Yastremskiy #:

Of course not, I meant that the array size is always known or can be known. And it can and must be controlled for index overrun.

You can control it, but it is not always necessary...

 
Alexey Viktorov #:

Controlling is possible, but not always necessary....

Hehe, then start after going beyond the limits))))
 
Valeriy Yastremskiy #:
Hehe, then start after going beyond)))))

Here's a look...

Forum on trading, automated trading systems and testing trading strategies.

Questions from beginners MQL5 MT5 MetaTrader 5

Alexey Viktorov, 2023.06.27 21:19

What is the problem? Declare an array temp[] and copy 30 elements into it and look for the index of the minimum/maximum value. And if at the end there will be less than 30, it will copy how many are left. And in this case, I'd rather use the while() loop.


Why should I control the size of the temp[] array?

You should control the size of the array from where we copy to temp[], I don't argue... But why do I need to control the size of the array where we are looking for the maximum\minimum?

 
Remind me, please, if there is a call of web socket connection from DLL called by EA, is it necessary to allow host address in terminal settings?
 
leonerd terminal settings?

Yes, the terminal only pokes through the allowed ones explicitly.

 
Valeriy Yastremskiy #:

Yeah, the terminal is only poking around the authorised ones.

So it's not the terminal that's poking around, it's the DLL.

 
leonerd #:

So it's not the terminal that's going to get involved, it's the DLL.

A dll does not need an authorised host in mt. it is enough to allow the use of a dll in mt. and the dll itself can do absolutely anything.

 
Can you tell me how to open a file, except ShellExecuteW through dll import? Is there a similar function in winapi.mqh?
 

Could you please tell me where this code is not working correctly? It reads records randomly as it wants, doesn't find everything, and gives new results at a new start.

//+------------------------------------------------------------------+
//|                                                      ProjectName |
//|                                      Copyright 2020, CompanyName |
//|                                       http://www.companyname.net |
//+------------------------------------------------------------------+
input int                  RULE1  = 0;
input int                  RULE2  = 0;
input int                  RULE3  = 0;
input int                  RULE4  = 0;
input bool                 FastComb  = 1;
input int                  FileLine= 20000;
input string               InpFileName="Report.csv";
//+------------------------------------------------------------------+
//| Structure Positions                                              |
//+------------------------------------------------------------------+
struct STRUCT_POSITION
  {
   ENUM_POSITION_TYPE pos_type;              // position type
   bool              waiting_transaction;    // waiting transaction, "true" -> it's forbidden to trade, we expect a transaction
   ulong             waiting_order_ticket;   // waiting order ticket, ticket of the expected order
   bool              transaction_confirmed;  // transaction confirmed, "true" -> transaction confirmed
   //--- Constructor
   STRUCT_POSITION()
     {
      pos_type                   = WRONG_VALUE;
      waiting_transaction        = false;
      waiting_order_ticket       = 0;
      transaction_confirmed      = false;
     }
  };
STRUCT_POSITION SPosition[];
///////////////////////////
struct Report
  {
   long              Pass;
   double            Result;
   double            Profit;
   double            Payoff;
   double            ProfitFactor;
   double            RecoveryFactor;
   double            SharpeRatio;
   long              Custom;
   double            EquityDD;
   long              Trades;
   long               Field1;
   long               Field2;
   long               Field3;
   long               Field4;
   long               Field5;
   long               Field6;
   long               Field7;
   long               Field8;
   long               Field9;
  };
long ProfitComb[20001][10];
///////////////////////////
//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
int OnInit()
  {
   if(FastComb)
     {
      ArrayInitialize(ProfitComb,-1);
      ReportListComb();
      int FindComb=0;
      for(int i=0; i<=FileLine; i++)
        {
         if(RULE1==ProfitComb[i][1] && RULE2==ProfitComb[i][2] && RULE3==ProfitComb[i][3] && RULE4==ProfitComb[i][4])
           {
            FindComb=1;
            break;
           }
        }
      if(FindComb==0 && RULE1!=0)
         return(INIT_PARAMETERS_INCORRECT);
     }
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
void ReportListComb()
  {
   Report ReportStr[];
   ResetLastError();
   ArrayResize(ReportStr,FileLine);
   string subfolder="Data";
   int file_handle=FileOpen(subfolder+"\\Report.csv",FILE_READ|FILE_WRITE|FILE_CSV|FILE_ANSI|FILE_COMMON,';');
   if(file_handle!=INVALID_HANDLE)
     {
      int i=0;
      while(!FileIsEnding(file_handle))
        {
         i++;
         ReportStr[i].Pass=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Result=StringToDouble(FileReadString(file_handle));
         ReportStr[i].Profit=FileReadNumber(file_handle);
         ReportStr[i].Payoff=FileReadNumber(file_handle);
         ReportStr[i].ProfitFactor=FileReadNumber(file_handle);
         ReportStr[i].RecoveryFactor=FileReadNumber(file_handle);
         ReportStr[i].SharpeRatio=FileReadNumber(file_handle);
         ReportStr[i].Custom=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].EquityDD=FileReadNumber(file_handle);
         ReportStr[i].Trades=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field1=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field2=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field3=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field4=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field5=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field6=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field7=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field8=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));
         ReportStr[i].Field9=StringToInteger(DoubleToString(FileReadNumber(file_handle),0));

         ProfitComb[i][1]=ReportStr[i].Field1;
         ProfitComb[i][2]=ReportStr[i].Field2;
         ProfitComb[i][3]=ReportStr[i].Field3;
         ProfitComb[i][4]=ReportStr[i].Field4;
         ProfitComb[i][5]=ReportStr[i].Field5;
         ProfitComb[i][6]=ReportStr[i].Field6;
         ProfitComb[i][7]=ReportStr[i].Field7;
         ProfitComb[i][8]=ReportStr[i].Field8;
         ProfitComb[i][9]=ReportStr[i].Field9;
        }
      FileClose(file_handle);
     }
   else
      PrintFormat("Не удалось открыть файл %s, Код ошибки = %d",InpFileName,GetLastError());
  }
//+------------------------------------------------------------------+
 

I can't understand what rates_total and prev_calculated mean in the end.

The documentation says: The first parameter rates_total contains the number of bars available to the indicator for calculation, and corresponds to the number of bars available on the chart.

For example MA5, average of 5 bars, set to display 100 bars. Then the indicator will calculate from the 104th to the 100th bar and will start drawing the line from the 100th bar. Then rates_total=5, or 100, or 104?

Reason: