Channel N Bars

ÿþ//+------------------------------------------------------------------+

//|                                               Channel N Bars.mq5 |

//|                              Copyright © 2022, Vladimir Karputov |

//|                      https://www.mql5.com/en/users/barabashkakvn |

//+------------------------------------------------------------------+

#property copyright "Copyright © 2022, Vladimir Karputov"

#property link      "https://www.mql5.com/en/users/barabashkakvn"

#property version   "1.003"

#property indicator_chart_window

#property indicator_buffers 2

#property indicator_plots   2

//--- plot Lowest

#property indicator_label1  "Lowest"

#property indicator_type1   DRAW_LINE

#property indicator_color1  clrYellowGreen

#property indicator_style1  STYLE_DOT

#property indicator_width1  1

//--- plot Highest

#property indicator_label2  "Highest"

#property indicator_type2   DRAW_LINE

#property indicator_color2  clrYellowGreen

#property indicator_style2  STYLE_DOT

#property indicator_width2  1

//+------------------------------------------------------------------+

//| Enum Price                                                       |

//+------------------------------------------------------------------+

enum ENUM_PRICE

  {

   hl=0,    // high low

   oc=1,    // open close

  };

//--- input parameters

input int         InputNBars  = 9;  // N Bars

input ENUM_PRICE  InpPrice    = oc; // Cannel price

//--- indicator buffers

double   LowestBuffer[];

double   HighestBuffer[];

//+------------------------------------------------------------------+

//| Custom indicator initialization function                         |

//+------------------------------------------------------------------+

int OnInit()

  {

//--- indicator buffers mapping

   SetIndexBuffer(0,LowestBuffer,INDICATOR_DATA);

   SetIndexBuffer(1,HighestBuffer,INDICATOR_DATA);

//--- set accuracy

   IndicatorSetInteger(INDICATOR_DIGITS,Digits());

//---

   return(INIT_SUCCEEDED);

  }

//+------------------------------------------------------------------+

//| Custom indicator iteration function                              |

//+------------------------------------------------------------------+

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[])

  {

   if(rates_total<InputNBars)

      return(0);

//---

   int limit=prev_calculated-1;

   if(prev_calculated==0)

      limit=InputNBars;

   for(int i=limit; i<rates_total; i++)

     {

      if(InpPrice==hl)

        {

         LowestBuffer[i]=low[ArrayMinimum(low,i-InputNBars+1,InputNBars)];

         HighestBuffer[i]=high[ArrayMaximum(high,i-InputNBars+1,InputNBars)];

        }

      else

        {

         LowestBuffer[i]=close[ArrayMinimum(close,i-InputNBars+1,InputNBars)];

         HighestBuffer[i]=open[ArrayMaximum(open,i-InputNBars+1,InputNBars)];

        }

     }

//--- return value of prev_calculated for next call

   return(rates_total);

  }

//+------------------------------------------------------------------+