EA disappears off chart when this library function is applied

[Bartlomiej Winter]

Hi all!

Thank you for looking at this thread. I'm writing some basic indicators in MQL5, and I am currently writing one for a simple average true range with no smoothing. Compiling the code leads to no errors or warnings. For some reason when I apply the EA to a chart it loads on fine but then on the next tick it disappears with no warning! I attached my code here, maybe there is something wrong with it?

Thank you for looking!

//+------------------------------------------------------------------+
//|                                      avg_true_range_function.mq5 |
//|                        Copyright 2018, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property library
#property copyright "Copyright 2018, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
//+------------------------------------------------------------------+
//| My function                                                      |
//+------------------------------------------------------------------+
// int MyCalculator(int value,int value2) export
//   {
//    return(value+value2);
//   }
//+------------------------------------------------------------------+
double avg_true_range_function(int no_candles) export
  {

//Creates a struct where the information about the candles (e.g. price) will be stored.
   MqlRates PriceInfo[];
//Sorts it from the current candle to the oldest candle
   ArraySetAsSeries(PriceInfo,true);
//Copies the price information into the array
   double Data=CopyRates(Symbol(),PERIOD_CURRENT,0,Bars(Symbol(),PERIOD_CURRENT),PriceInfo);

//Creating 'buy' arrays
   double high_price[]; //Store the high price
   double low_price[]; //Store the low price
   double close_price[]; //Store the close price
   ArrayResize(high_price,no_candles);
   ArrayResize(low_price,no_candles);
   ArrayResize(close_price,no_candles);

   for(int i=0; i<no_candles+1; i=i+1)
     {
      high_price[i]=PriceInfo[i+1].high;
      low_price[i]=PriceInfo[i+1].low;
      close_price[i]=PriceInfo[i+1].close;
     }
   double tr[]; //Array to store the value of the true range
   double tr_values_store[],avg_tr=0,high_minus_low=0,high_minus_close=0,low_minus_close=0;
   ArrayResize(tr,no_candles);
   ArrayResize(tr_values_store,3);
   for(int i=no_candles;i>0;i=i-1)
   {
    high_minus_low = high_price[i-1]-low_price[i-1];
    high_minus_close = high_price[i-1]-close_price[i];
    low_minus_close = low_price[i-1]-close_price[i];
    tr_values_store[0] = high_minus_low;
    tr_values_store[1] = high_minus_close;
    tr_values_store[2] = low_minus_close;
    
    tr[i-1] = ArrayMaximum(tr_values_store,WHOLE_ARRAY,0);
   }
   
   double tr_sum=0;
   for(int i=0;i<no_candles;i=i+1)
   {
   tr_sum = tr_sum + tr[i];
   }
   avg_tr = tr_sum/no_candles;
   
   return avg_tr;

  }
//+------------------------------------------------------------------+

[Alain Verleyen]

Your title talk about an EA, your post about an indicator, and you posted a library code. Make up your mind and be clearer if you need help.

And check the logs to see why the EA was removed from the chart.