Indicator Calculation Loops.

[Tom Clayson]

Could someone please explain how to ensure the indicator calculates all bars available on the first run, and then only the bar that most recently appears. My indicator calculates what I want on the first run, but then does nothing. I can't figure out why.

if(_BarsCalculated==0) {
      StartIndex = _BarsTotal-2;
      FinishIndex = 1;
   }   
   else {
      StartIndex = 1;
      FinishIndex = 1;
   } 
   
   //TODO: Adjust arrow width depending on current chart zoom. 
   if(_BarsTotal<StartIndex) {
      return(0);
   }
   else {
      if(FirstRun) {
      
         ArrayInitialize(HighCloseBullPattern,EMPTY_VALUE);
         ArrayInitialize(MidCloseBullPattern,EMPTY_VALUE);
         ArrayInitialize(LowCloseBullPattern,EMPTY_VALUE);
         ArrayInitialize(HighCloseRangePattern,EMPTY_VALUE);
         ArrayInitialize(MidCloseRangePattern,EMPTY_VALUE);
         ArrayInitialize(LowCloseRangePattern,EMPTY_VALUE);
         ArrayInitialize(HighCloseBearPattern,EMPTY_VALUE);
         ArrayInitialize(MidCloseBearPattern,EMPTY_VALUE);
         ArrayInitialize(LowCloseBearPattern,EMPTY_VALUE);

         // Set the price arrays to match with the indicator arrays

         FirstRun=false;
      }
   }

   for(int Bar=StartIndex; Bar>=FinishIndex; Bar--) {
       Sentiment = CandleSentiment(Bar,Bar+1,Bar1RangePercent,Bar2RangePercent,O,H,L,C);
   }

[Pasi Hakamaki]

whitebloodcell:

Could someone please explain how to ensure the indicator calculates all bars available on the first run, and then only the bar that most recently appears. My indicator calculates what I want on the first run, but then does nothing. I can't figure out why.

I recommend you read the documentation. This is good article on it. The loop you want is:

int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
  {
//---
   int limit;
   if(prev_calculated==0)   //--- If it is the first call go through all bars
      limit=0;
   else
      limit=rates_total-1;  //--- Else just check the most current bar that has not yet finished

   for(int i=limit;i<rates_total-1;i++)
     {
      //--- Your logic here
     }
//--- return value of prev_calculated for next call
   return(rates_total);

[Tom Clayson]

Candles:

I recommend you read the documentation. This is good article on it. The loop you want is:

Thanks for your help. I wanted to calculate from left to right, and thought I needed to decrement therefore, but I was confused in the way the bars are numbered.

[Pasi Hakamaki]

whitebloodcell:
Thanks for your help. I wanted to calculate from left to right, and thought I needed to decrement therefore, but I was confused in the way the bars are numbered.

If you want to do it this way then you can use ArraySetAsSeries to change the indexing order.