Tradestation 2000i: Standard Error Channels

The following TradeStation code seams to do the trick:
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{This Indicator plots Linear Regression Line Provided By: Omega Research, Inc. (c) Copyright 1999

Modified By: Clyde Lee (c) 2000,include parallel lines.

Add start date, start-end date

Definition.

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inputs: Length(60),

{This is set to difference in Start & End dates if both are specified and is ignored
then}

{if set to zero and begin (but not end) date is }
{specified then length is from begin date to}
{last bar on chart}

{NOTE: If length is specified and begin/end date}

{and time are set to zero then trendline and the}

{channel lines if specified are calculated (and}

{in real time updated) from the last bar on the}

{chart backwards for length specified.}

BegDate(0), {YYYMMDD-if specified fixes begin of compute}

BegTime(0), {Set to zero to ignore time }

EndDate(0), {YYYMMDD-if specified fixes end of compute}

EndTime(0), {Set to zero to ignore time}

ColSizMd(6.1), {x.y x=color y=line size (0-6) for mid line }

{Black=1, Blue=2, Cyan=3, Green=4,}

{Magenta=5, Red=6, Yellow=7, White=8,}

{DarkBlue=9}

{DarkCyan=10, DarkGreen=11, DarkMagenta=12,}

{DarkRed=13, DarkBrown=14, DarkGray=15,} {LightGray=16}

{You can use: red+. 1 (red color, size=1)}

{if you do this DO NOT FORGET THE DECIMAL B4 LINE}
ExtRight(True), {Set false for no extension to mid/channel lines }
ChanWide(2), {Multiplier of StdDev(c,Length) to set width }
ColSizCh(2.1); {x.y x=color y=line size for channel lines }

variables:
LRV(0), {Current linear regression value} LRVAgo(0),
{Linear regression value at begin of lines}
TLLRV(0),TLLRV1(0),TLLRV2(0), {TL ID's for mid and channel lines} Flag(0),
{basically the mode of operation} ChanStdD(0),
{Use initial standard deviation computation}
UseLength(Iff(BegDate>0,0,Length)), UseEndDate(EndDate),
UseEndTime(EndTime), UseBeginDate(BegDate),
UseBeginTime(BegTime), UseColor(ColSizMd-1),
BeginBar(0);Variables: MidColor(IntPortion(ColSizMd)),
MidSize (IntPortion((ColSizMd-MidColor)*10)),
ChnColor(IntPortion(ColSizCh)), ChnSize
(IntPortion((ColSizCh-ChnColor)*10));

If UseBeginDate>0 then begin
{If begin date then find out and set BeginBar variable} If
Date>=BegDate and Time>=BegTime and BeginBar=0 then
begin BeginBar=CurrentBar; End Else if
BeginBar>0 then begin {Begin date detected so now look
for end date and set when found} If EndDate>0 or
lastbaronchart then begin if (Date>=EndDate
and Time>=EndTime) or LastBarOnChart then
begin
UseLength=CurrentBar-BeginBar;
UseEndDate=Date;
UseEndTime=Time;
UseBeginDate=0;
end else if date<EndDate then
UseLength=0; End Else If
CurrentBar=BeginBar+Length then begin {If
length specified & no end date just set
end}
UseLength=Length;
UseEndDate=Date;
UseEndTime=Time;
UseBeginDate=0; End; End;End;

{Once we have a good length then proceed to
compute/draw lines}If UseLength>0 then begin
if LastBarOnChart and EndDate=0 and Flag=0 then
begin Flag=1 ; end ; if
Date=UseEndDate and (Time=UseEndTime or UseEndTime=0) and Flag=0 then
begin Flag=2 ; end ; if
Flag=1 or Flag=2 then begin

LRV
=LinearRegValue(Close,UseLength,0) ;
Value1=LinearRegSlope(Close,UseLength) ;
LRVAgo=LRV-(UseLength-1)*Value1;

If Flag[1]=0 then
begin {If this is first time to draw then we must define the trendlines}
TLLRV=TL_New(Date[UseLength-1],Time[UseLength-1],LRVAgo,Date,Time,LRV)
; TL_SetColor (TLLRV,MidColor)
; TL_SetSize
(TLLRV,MidSize); TL_SetExtLeft(TLLRV,false)
;
Plot1(LRV,"ell");
{SetPlotColor(1,UseColor);} If ChanWide>0
then begin {Setup channel lines if
specified}
ChanStdD=StdDev(c,UseLength)*ChanWide;
TLLRV1=TL_New(Date[UseLength-1],Time[UseLength-1],LRVAgo+ChanStdD,Date,Time,LRV+ChanStdD)
;
TLLRV2=TL_New(Date[UseLength-1],Time[UseLength-1],LRVAgo-ChanStdD,Date,Time,LRV-ChanStdD)
; End;
End; if Flag=1 then
begin {If not first time and we are moving
lines then just update trendlines}
TL_SetBegin(TLLRV,Date[UseLength-1],Time[UseLength-1],LRVAgo)
; TL_SetEnd (TLLRV,Date,Time,LRV)
;
Plot1(LRV,"ell"); {Move start/end of channel
lines if specified} If ChanWide>0 then
begin
TL_SetBegin(TLLRV1,Date[UseLength-1],Time[UseLength-1],LRVAgo+ChanStdD)
; TL_SetEnd
(TLLRV1, Date, Time, LRV+ChanStdD) ;
TL_SetBegin(TLLRV2,Date[UseLength-1],Time[UseLength-1],LRVAgo-ChanStdD)
; TL_SetEnd
(TLLRV2, Date, Time, LRV-ChanStdD);
End; end;
if Flag=2
then Flag=3 ;

{Set colors, extensions,
width of line for median line} TL_SetColor
(TLLRV,MidColor) ; TL_SetSize
(TLLRV,MidSize); TL_SetExtLeft(TLLRV,false)
; if ExtRight
then TL_SetExtRight(TLLRV,true)
else TL_SetExtRight(TLLRV,false) ; If
ChanWide>0 then begin {Set colors,
extensions, width of line for channel lines}
TL_SetColor (TLLRV1,ChnColor) ;
TL_SetColor (TLLRV2,ChnColor) ;
TL_SetSize (TLLRV1,ChnSize);
TL_SetSize (TLLRV2,ChnSize);
TL_SetExtLeft(TLLRV1,false) ;
TL_SetExtLeft(TLLRV2,false) ; if ExtRight then
begin
TL_SetExtRight(TLLRV1,true);
TL_SetExtRight(TLLRV2,true);
end else
begin TL_SetExtRight(TLLRV1,false)
; TL_SetExtRight(TLLRV2,false)
; end; End;
end ;

End; {End of loop waiting for end date if begin date specified}

{*** Copyright (c) 1991-2000 TradeStation. All rights reserved. ***}
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Have fun.

Derek