// Downloaded From https://www.WiseStockTrader.com
_SECTION_BEGIN("Pair ratio");
Ticker= ParamStr("Short ticker", "type in ticker");//short stock
////////////////////////////////////////////
tickersc=Foreign( ticker, "C");//Short stock
////////////////////////////////////////////
ratio=C/tickersc;
P=ratio;
Plot(p ," /"+ ticker,5,5);
///////////////////////////////////////////////////////
_SECTION_END();

_SECTION_BEGIN("Linear_Regression_Line_w__Std_Deviation_Channels");
//  Linear Regression Line with 2 Standard Deviation Channels Plotted Above and Below 
//  Written by Patrick Hargus, with critical hints from Marcin Gorzynski, Amibroker Technical Support 
//      Designed for use with AB 4.63 beta and above, using drag and drop feature.  
//  Permits plotting a linear regression line of any price field available on the chart for a period determined by the user.  
//     2 Channels, based on a standard deviation each determined by the user, are plotted above and below the linear regression line. 
// 		A look back feature is also provided for examining how the indicator would have appeared on a chart X periods in the past.    


P = ParamField("Price field",-1);
Daysback = Param("Period for Liner Regression Line",21,1,360,1);
shift = Param("Look back period",0,0,360,1); 


//  =============================== Math Formula =============================================================

x = Cum(1);
lastx = LastValue( x ) - shift; 
aa = LastValue( Ref(LinRegIntercept( p, Daysback), -shift) ); 
bb = LastValue( Ref(LinRegSlope( p, Daysback ), -shift) ); 
y = Aa + bb * ( x - (Lastx - DaysBack +1 ) ); 


// ==================Plot the Linear Regression Line ==========================================================


LRColor = ParamColor("LR Color", colorCycle ); 
LRStyle = ParamStyle("LR Style");

LRLine =  IIf( x > (lastx - Daysback) AND BarIndex() < Lastx, y, Null );
Plot( LRLine , "LinReg", LRCOLOR, LRSTYLE ); //  styleDots ); 

// ==========================  Plot 1st SD Channel ===============================================================

SDP = Param("Standard Deviation", 1.5, 0, 6, 0.1);
SD = SDP/2;

width = LastValue( Ref(SD*StDev(p, Daysback),-shift) );   // THIS IS WHERE THE WIDTH OF THE CHANELS IS SET  
SDU = IIf( x > (lastx - Daysback) AND BarIndex() < Lastx, y+width , Null ) ;
SDL = IIf( x > (lastx - Daysback) AND BarIndex() < Lastx, y-width , Null ) ;

SDColor = ParamColor("SD Color", colorCycle ); 
SDStyle = ParamStyle("SD Style");

Plot( SDU , "Upper Lin Reg", SDColor,SDStyle ); 
Plot( SDL , "Lower Lin Reg", SDColor,SDStyle ); 

//  ==========================  Plot 2d SD Channel ===============================================================

SDP2 = Param("2d Standard Deviation", 2.0, 0, 6, 0.1);
SD2 = SDP2/2;

width2 = LastValue( Ref(SD2*StDev(p, Daysback),-shift) );   // THIS IS WHERE THE WIDTH OF THE CHANELS IS SET  
SDU2 = IIf( x > (lastx - Daysback) AND BarIndex() < Lastx, y+width2 , Null ) ;
SDL2 = IIf( x > (lastx - Daysback) AND BarIndex() < Lastx, y-width2 , Null ) ;

SDColor2 = ParamColor("2 SD Color", colorCycle ); 
SDStyle2 = ParamStyle("2 SD Style");

Plot( SDU2 , "Upper Lin Reg", SDColor2,SDStyle2 ); 
Plot( SDL2 , "Lower Lin Reg", SDColor2,SDStyle2 ); 

// ============================ End Indicator Code ==============================================================
_SECTION_END();