mql-for-begginers/Indicators/Free Indicators/Keltner Channel.mq5
2025-07-22 18:30:17 +03:00

246 lines
8.7 KiB
MQL5

//+------------------------------------------------------------------+
//| Keltner Channel.mq5 |
//| Copyright 2009-2025, MetaQuotes Ltd |
//| https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "2009-2025, MetaQuotes Ltd"
#property link "http://www.mql5.com"
#property description "Keltner Channel"
#property indicator_chart_window
#property indicator_buffers 3
#property indicator_plots 3
#property indicator_type1 DRAW_LINE
#property indicator_color1 clrBlue
#property indicator_type2 DRAW_LINE
#property indicator_color2 clrGray
#property indicator_type3 DRAW_LINE
#property indicator_color3 clrRed
//--- labels
#property indicator_label1 "Upper Keltner"
#property indicator_label2 "Middle Keltner"
#property indicator_label3 "Lower Keltner"
//--- input parameters
input int InpEMAPeriod=20; // Period of EMA
input int InpATRPeriod=10; // Period of ATR
input double InpATRFactor=2.0; // ATR multiplier
input bool InpShowLabel=true; // Show price of level
//--- global variables for parameters
int ExtEMAPeriod;
int ExtATRPeriod;
double ExtATRFactor;
//--- indicator buffers
double ExtUppBuffer[];
double ExtEMABuffer[];
double ExtDwnBuffer[];
//--- indicator handles
int ExtEMAHandle;
int ExtATRHandle;
//--- unique prefix to identify indicator objects
string ExtPrefixUniq;
int ExtPeriod;
//+------------------------------------------------------------------+
//| Custom indicator initialization function |
//+------------------------------------------------------------------+
int OnInit()
{
//--- check for input values
if(InpEMAPeriod<10)
{
ExtEMAPeriod=20;
PrintFormat("Incorrect value for input variable InpEMAPeriod=%d. Indicator will use value=%d for calculations.",
InpEMAPeriod, ExtEMAPeriod);
}
else
ExtEMAPeriod=InpEMAPeriod;
if(InpATRPeriod<3)
{
ExtATRPeriod=10;
PrintFormat("Incorrect value for input variable InpATRPeriod=%d. Indicator will use value=%d for calculations.",
InpATRPeriod, ExtATRPeriod);
}
else
ExtATRPeriod=InpATRPeriod;
if(InpATRFactor<1.0)
{
ExtATRFactor=2.0;
PrintFormat("Incorrect value for input variable InpBandsDeviations=%f. Indicator will use value=%f for calculations.",
InpATRFactor, ExtATRFactor);
}
else
ExtATRFactor=InpATRFactor;
//--- define buffers
SetIndexBuffer(0, ExtUppBuffer);
SetIndexBuffer(1, ExtEMABuffer);
SetIndexBuffer(2, ExtDwnBuffer);
//--- indexes draw begin settings
PlotIndexSetInteger(0, PLOT_DRAW_BEGIN, InpEMAPeriod+1);
PlotIndexSetInteger(1, PLOT_DRAW_BEGIN, InpEMAPeriod+1);
PlotIndexSetInteger(2, PLOT_DRAW_BEGIN, InpEMAPeriod+1);
//--- set a 1-bar offset for each line
PlotIndexSetInteger(0, PLOT_SHIFT, 1);
PlotIndexSetInteger(1, PLOT_SHIFT, 1);
PlotIndexSetInteger(2, PLOT_SHIFT, 1);
//--- set drawing line empty value
PlotIndexSetDouble(0, PLOT_EMPTY_VALUE, 0.0);
PlotIndexSetDouble(1, PLOT_EMPTY_VALUE, 0.0);
PlotIndexSetDouble(2, PLOT_EMPTY_VALUE, 0.0);
//--- indicator name
IndicatorSetString(INDICATOR_SHORTNAME, "Keltner Channel");
//--- number of digits of indicator value
IndicatorSetInteger(INDICATOR_DIGITS, _Digits);
//--- create indicators
ExtEMAHandle=iMA(NULL, 0, InpEMAPeriod, 0, MODE_EMA, PRICE_CLOSE);
ExtATRHandle=iATR(NULL, 0, InpATRPeriod);
ExtPeriod=PeriodSeconds(_Period);
//--- prepare prefix for objects
string number=StringFormat("%I64d", GetTickCount64());
ExtPrefixUniq=StringSubstr(number, StringLen(number)-4);
ExtPrefixUniq=ExtPrefixUniq+"_KLT";
Print("Indicator \"Keltner Channels\" started, prefix=", ExtPrefixUniq);
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 this is the first calculation of the indicator
if(prev_calculated==0)
{
//--- populate the beginning values, for which the indicator cannot be calculated, with empty values
ArrayFill(ExtUppBuffer, 0, rates_total, 0);
ArrayFill(ExtEMABuffer, 0, rates_total, 0);
ArrayFill(ExtDwnBuffer, 0, rates_total, 0);
//--- get EMA values into the indicator buffer
if(CopyBuffer(ExtEMAHandle, 0, 0, rates_total, ExtEMABuffer)<0)
return(0);
//--- get ATR indicator values into a dynamic array
double atr[];
if(CopyBuffer(ExtATRHandle, 0, 0, rates_total, atr)<0)
return(0);
//--- shift from the beginning by the required number of bars
int start=MathMax(InpEMAPeriod, InpATRPeriod)+1;
//--- fill in the values of the upper and lower channel borders
for(int i=start; i<rates_total; i++)
{
ExtUppBuffer[i]=ExtEMABuffer[i]+InpATRFactor*atr[i];
ExtDwnBuffer[i]=ExtEMABuffer[i]-InpATRFactor*atr[i];
}
//--- succesfully calculated
return(rates_total);
}
//--- if the indicator has previously been calculated, calculate values for the last 2 bars
int start=prev_calculated-2;
for(int i=start; i<rates_total; i++)
{
//--- for element-by-element copying from the indicator, use the reverse index
int reverse_index=rates_total-i;
//--- get indicator values
double ema[];
if(CopyBuffer(ExtEMAHandle, 0, reverse_index, 1, ema)<0)
return(prev_calculated);
double atr[];
if(CopyBuffer(ExtATRHandle, 0, reverse_index, 1, atr)<0)
return(prev_calculated);
//--- write values into buffers
ExtEMABuffer[i]=ema[0];
ExtUppBuffer[i]=ema[0]+InpATRFactor*atr[0];
ExtDwnBuffer[i]=ema[0]-InpATRFactor*atr[0];
}
//--- draw labels on levels
if(InpShowLabel)
{
ShowPriceLevels(time[rates_total-1]+ExtPeriod, rates_total-1);
ChartRedraw();
}
//--- succesfully calculated
return(rates_total);
}
//+------------------------------------------------------------------+
//| Custom indicator deinitialization function |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
{
//--- delete all our graphical objects after use
Print("Indicator \"Keltner Channels\" stopped, delete all objects with prefix=", ExtPrefixUniq);
ObjectsDeleteAll(0, ExtPrefixUniq, 0, OBJ_ARROW_RIGHT_PRICE);
ChartRedraw(0);
}
//+------------------------------------------------------------------+
//| Show prices' levels |
//+------------------------------------------------------------------+
void ShowPriceLevels(datetime time, int last_index)
{
ShowRightPrice(ExtPrefixUniq+"_Upp", time, ExtUppBuffer[last_index], clrBlue);
ShowRightPrice(ExtPrefixUniq+"_EMA", time, ExtEMABuffer[last_index], clrGray);
ShowRightPrice(ExtPrefixUniq+"_DWN", time, ExtDwnBuffer[last_index], clrRed);
}
//+------------------------------------------------------------------+
//| Create or Update "Right Price Label" object |
//+------------------------------------------------------------------+
bool ShowRightPrice(const string name, datetime time, double price, color clr)
{
if(!ObjectCreate(0, name, OBJ_ARROW_RIGHT_PRICE, 0, time, price))
{
ObjectMove(0, name, 0, time, price);
return(false);
}
//--- make the label size adaptive
long scale=2;
if(!ChartGetInteger(0, CHART_SCALE, 0, scale))
{
//--- output an error message to the Experts journal
Print(__FUNCTION__+", ChartGetInteger(CHART_SCALE) failed, error = ", GetLastError());
}
int width=scale>1 ? 2:1; // if chart scale > 1, then label size = 2
ObjectSetInteger(0, name, OBJPROP_COLOR, clr);
ObjectSetInteger(0, name, OBJPROP_STYLE, STYLE_SOLID);
ObjectSetInteger(0, name, OBJPROP_WIDTH, width);
ObjectSetInteger(0, name, OBJPROP_BACK, false);
ObjectSetInteger(0, name, OBJPROP_SELECTABLE, false);
ObjectSetInteger(0, name, OBJPROP_SELECTED, false);
ObjectSetInteger(0, name, OBJPROP_HIDDEN, true);
ObjectSetInteger(0, name, OBJPROP_ZORDER, 0);
return(true);
}
//+------------------------------------------------------------------+