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Herman,
I really donīt 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 is a huge negative number
Another 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 parentheses
AFL 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@x...]
> > 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@xxxx, "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! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
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