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It's a pretty sad comment when evidence shows a competitor going to
greater lengths to address a Trade Station user's concerns than does
Omega.
No wonder we're seeing such positive reaction (even from Pierre :-)
toward banding together to advertise the existance of the Omega List to
newbies. What better way than that to get Omega to understand Customers
are not Mushrooms...to be kept in the Dark and fed BS as if they were
some 4H Project run amuck.
Dave
> Subject:
> RE: TL_VB & EL Square Root Functions
> Date:
> Fri, 18 Sep 1998 21:19:31 -0400
> From:
> "Mark J. Cerar" <mcerar@xxxxxxxxx>
> To:
> "Scientific Approaches" <sci@xxxxxxxxxx>, "TradeLab Mail List" <TradeLab@xxxxxxxxxx>
>
>
> Early this year, after having read a piece in "Technical Analysis of Stocks
> & Commodities" ( p. 67, January, 1998), I tried to reproduce the Correlation
> function in TS. In order to calculate the correlation coefficient you need
> to calculate the square root of the variance. I could not get the results
> of my TS function to match the results obtained in Excel using identical raw
> data. When I wrote to EasyLang Support, the technical support rep simply
> brushed me off saying there was a problem in my code and that they don't
> correct users faulty program code. He told me that one of the Omega
> Solution Providers could help me. Now I understand why I couldn't work but
> couldn't the rep simply have told me this instead of feeding me BS.
>
> Mark.
>
> > -----Original Message-----
> > From: Scientific Approaches [mailto:sci@xxxxxxxxxx]
> > Sent: Sunday, September 13, 1998 3:59 PM
> > To: TradeLab Mail List
> > Subject: TL_VB & EL Square Root Functions
> >
> >
> > Easy Language has a SquareRoot(Num) function that returns the Single
> > Precision square root of a Single Precision value passed in the
> > variable Num
> > . The function is described on Page 289 of the TS4 TradeStation User's
> > Manual as follows:
> >
> > "Returns the square root of a number (num).
> > Num may be any numeric expression."
> >
> > That statement is not true. Num must contain a positive number or a valid
> > numeric expression that returns a positive number to avoid unrecoverable
> > catastrophic TradeStation failure.
> >
> > Visual Basic has a similar square root function named Sqr(Num).
> > It accepts
> > and returns Double Precision floating point values. It calculates square
> > roots to twice the precision of the Easy Language function. It
> > also causes
> > unrecoverable catastrophic failure if a negative number is passed to it
> > unless error trapping is used.
> >
> > Easy Language doesn't have error trapping. Error trapping is one of the
> > many advantages of Visual Basic compared to Easy Language. It is
> > especially
> > important in real-time trading applications where a bad datafeed tick can
> > otherwise cause a trading system to crash.
> >
> > Visual Basic error trapping is very easy to use. There are
> > several options.
> > This is an example of one way it could be used with the Sqr(Num) function
> > to avoid catastrophic failure:
> >
> > Num = {Some mathematical expression}
> >
> > On Error GoTo ErrorHandler
> > SquareRoot = Sqr(Num)
> > On Error GoTo 0
> >
> > { More lines of code as necessary }
> >
> > Exit Function
> >
> > ErrorHandler:
> > MsgBox "Illegal value passed to Sqr(Num).", vbOkOnly
> > Exit Function
> >
> > The "On Error GoTo ErrorHandler" statement activates error trapping. "On
> > Error GoTo 0" switches error trapping back off. The ErrorHandler
> > routine is
> > called if an error occurs between the two statements.
> >
> > The ErrorHandler routine can do whatever you want it to do if there is an
> > error. It can contain a "Resume Next" statement to simply skip
> > the line of
> > code that caused the error and continue. That will avoid catastrophic
> > failure, but the user will not be notified that an error occurred
> > and a line
> > of code was skipped. That is acceptable in some cases, but generally the
> > user should be notified that something went wrong.
> >
> > Visual Basic has a pop-up Message Box that is useful for user
> > notification.
> > The MsgBox statement in the ErrorHandler routine above pops the
> > Message Box
> > on the screen and displays the message that follows between the
> > quote marks.
> > The message can be anything you want. "vbOkOnly" causes the
> > Message Box to
> > display only an "Ok" button the user can click to make the box go
> > away after
> > the message has been read.
> >
> > -Bob Brickey
> > Scientific Approaches
> > sci@xxxxxxxxxx
> >
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