Hi, the code below is part of an afl written by Patrick Hargus and is
on
the AFL Library:
== partial code
P = ParamField("Price
field",-1);
Daysback = Param("Period for Liner Regression
Line",21,1,240,1);
shift = Param("Look back period",0,0,240,1);
// =============================== 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 ) );
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 );
======================
I was wondering if anyone could
help to plot the value of the last
lower regression line SDL as a band
instead of a channel...
I know there's the "shift" parameter but I'm
just not sure how to make
it change for each bar.
Thanks a
lot.