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Copy and paste formula below.


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LinReg Indicator/Slope
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{ Linear Regression Indicator/Slope MS formula }
{ Precision accumulation errors courtesy of
  MetaStock's Cum() single-precision function }
{ ©Copyright 2003-2004 Jose Silva }
{ For private use only }
{ http://www.metastocktools.com }

{ User inputs }
pds:=Input("Linear Regression periods",
 2,2520,21);
plot:=Input("Linear Regression:  [1]Indicator,  [2]Slope",1,2,1);
x:=Input("[1]Open, [2]High, [3]Low, [4]Close, [5]WgtCl, [6]P",1,6,4);
x:=If(x=1,O,If(x=2,H,If(x=3,L,If(x=5,WC(),If(x=6,P,C)))));

{ Lin Reg Slope }
counter:=Cum(1)-pds;
y:=pds*Sum(counter*x,pds)
 -Sum(counter,pds)*Sum(x,pds);
z:=pds*Sum(Pwr(counter,2),pds)
 -Pwr(Sum(counter,pds),2);
z:=
 LastValue(ValueWhen(1,Cum(IsDefined(z))=1,z));
LRS:=y/z;

{ Lin Reg Indicator - LR trendline end point }
LRI:=LRS*pds-LRS*(pds+1)/2+Mov(x,pds,S);

{ Lin Reg trendline start point }
LRstart:=Ref(LRI-LRS*(pds-1),pds-1);

{ Plot }
If(plot=1,LRI,LRS)

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