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not in this universe :) It may not, in fact,
matter since the exponentiation operator always (by some other convention?)
follows the operand. Actually the "unitary" is a relatively new term (in
the past 20 years) jumping out after I was well out of grad school (in
mathematical physics) and before the programmers began to worry about the
difference between subtraction and what I always interpreted as a simple
negative number - the computer worries about such things, people
don't. (I do realize the mathematical distinction
has been around for centuries - just ignored like most math in the real world
until it found a use.)
BTW - Multiplication and division are not generally
on the same level ( My Dear Aunt Sally) for the antiques in the group; although,
when in doubt most simply just hammer in parens by reflex - similar to the way a
horse runs first and asks questions latter....
I still think that this is a simple documentation
error on TJ's part , and,personally, I find that comforting
:)
Cheers,
Richard
<BLOCKQUOTE
>
----- Original Message -----
<DIV
>From:
Steve Dugas
To: <A title=amibroker@xxxxxxxxxx
href="">amibroker@xxxxxxxxxxxxxxx
Sent: Monday, April 29, 2002 8:34
PM
Subject: Re: [amibroker] Re: Are your
Composites accurate???
It just occurred to me - maybe they are on the same level
(like multiplication and division), so it does the negation first becauseit
comes to it first?
Steve
<BLOCKQUOTE
>
----- Original Message -----
<DIV
>From:
Steve Dugas
To: <A title=amibroker@xxxxxxxxxxxx
href="">amibroker@xxxxxxxxxxxxxxx
Sent: Monday, April 29, 2002 9:08
PM
Subject: Re: [amibroker] Re: Areyour
Composites accurate???
Hi DT,
I must be missing something. I tried your plot, and
-1^10 did evaluate to 1, like you say. But, if exponentiation takes
precedence over negation (as shown in your table), how come it doesnt
evaluate to -1, like this? :
-1^10 = -(1^10) = -(1)
= -1
Steve
<BLOCKQUOTE
>
----- Original Message -----
<DIV
>From:
dtsokakis
To: <A
title=amibroker@xxxxxxxxxxxxxxx
href="">amibroker@xxxxxxxxxxxxxxx
Sent: Monday, April 29, 2002 12:16
PM
Subject: [amibroker] Re: Are your
Composites accurate???
Herman,I really don´t know how do you realise
things.Well, -1^10 is equal to 1.[It acts like (-1)^10 because of
priorities in operators**[try Plot(-1^10,"",1,1);]-1*10^10 isa
huge negative numberAnother Amibroker expression is -1e10, also
negative enough.Your formula was not correct, because it was excuding
stocks with open==1 from counting.[see previous mails to
you]DT**Operator precedence and the parenthesesAFL supports
parentheses in formulas. Parentheses can be used to control the
operation precedence (the order in which the operators are
calculated). AmiBroker always does operations within the innermost
parentheses first. When parentheses are not used, the precedence is as
follows (higher precedence listed first): No Symbol Meaning
1 ^ Exponentiation 2 - Negation - Unary minus 3 *
Multiplication 4 / Division 5 + Addition 6 -
Subtraction 7 < Less than 8 > Greater than 9
<= Less than or equal to 10 >= Greater than or equal to
11 == Equal to 12 != Not equal to 13 NOT Logical "Not"
14 AND Logical "And" 15 OR Logical "Or" 16 = Variable
assignment operator The expression H + L / 2; (without
parenthesis) would be calculated by AmiBroker as "L / 2" plus "H",
since division has a higher precedence. This would result in a much
different value than (H + L)/2; --- In amibroker@xxxx,
"Herman van den Bergen" <psytek@xxxx> wrote:> >
-----Original Message-----> > From: dtsokakis
[mailto:TSOKAKIS@xxxx]> > Sent: Sunday, April 28, 2002 11:13
AM> > To: amibroker@xxxx> > Subject: [amibroker] Re:
Are your Composites accurate???> >> >> >
Herman,> > I just noticed that your EMPTY is -1^10, ie equal to
1.> > So, your equivalent formula is> > EMPTY =
1;> > Just realized that -1^10 is not equal to 1 but is-1 *
10^10> > perhaps my code was OK anyway?> >
Take care,> Herman.> > > > >
> AddToComposite(IIf(Open == 1,0,1),"~DataPresent","v",3);> >
Do you have in the group of your gif some stocks with open==1 ?>
> This would give some explanation.> > DT> > PS The
huge negative symbol in AFL is -1e10> > --- In amibroker@xxxxxx,
"dtsokakis" <TSOKAKIS@xxxx> wrote:> > > Of course I
receive an identical result list with your> > > EMPTY =
-1^10;> > > AddToComposite(IIf(Open ==
EMPTY,0,1),"~DataPresent","v",3);> > > Buy= 0;>>
> f=Foreign("~datapresent","v");> > >
Filter=f!=101;> > > AddColumn(f,"");> > >
EXACTLY the same results.> > > To avoid any misuderstanding
:your formula works, I just think> > > Amibroker does not use
the open==EMPTY hypothesis, because if the> > > ADLAC is
not present on 16/4/2002, there is no reference for ADLAC>>
> this date.> > > My opinion is from experience, Tomasz
knows how AddToComposite()> > > works.> > >
DT> > > --- In amibroker@xxxx, "Dimitris Tsokakis"
<TSOKAKIS@xxxx> wrote:> > > > I respectfully
disagree. If you are not concerned about bar-by-> >
bar> > > accuracy> > > > than you are
correct. In that case the "1" method works fine. As> > >
long as you> > > > know that this method will pick up
holes of several days but that> > > it will> >
> > not pick up single bar holes.> > > >>
> > >> > > > Herman,> > > > Of
course we speak for daily search, bar-by-bar.> > > > I
have in my ^NDX 4 experimental holes on> > > > 6/1/2000
[1], 15/2/2000 [1] and 1/3/2000[2]> > > > plus the missing
ADLAC after 15/4/2002.> > > > As you see from the
exploration, the population> > > > is different from 101
exactly these dates.> > > > I do not understand the
conditions of your graph.> > > > The> > >
> AddToComposite(1,"~count","v");> > > > Buy=0;>
> > > scans bar-by-bar every stock for each date.> >
> > If the stock is present, it adds an 1 and moves to the next
stock.> > > > If ADLAC is not present on 16/4/2002,
then the sum will be 100> > > > for the certain
date.> > > > It is impossible to have a 20% error, there
should be another> > > > reason for your results.>
> > > Dimitris Tsokakis> >> >>
>> >> >> > Your use of Yahoo! Groupsis
subject to <A
href="">http://docs.yahoo.com/info/terms/>
>> >Your use of Yahoo! Groups is subject
to the Yahoo! Terms of
Service. Your use of Yahoo! Groups is
subject to the Yahoo! Terms of
Service. Your
use of Yahoo! Groups is subject to the <A
href="">Yahoo! Terms of Service.
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