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Hello,
The floating point arithmetic is sometime
strange :-)
As you probably know decimal fractions
could not be represented
accuratelly in the IEEE floating point
format (only powers of 2
could be represented so 0.5, 0.25,0.125,
0.0625 ... are always precise).
Unfortuntatelly <FONT face="ArialGreek"
size=2>0.1 can not be represented 100% accuratelly as
a power of 2. So it is in fact
0.1000000000000000001 or something like that.
Then iterating this leads to
0.800000000000000008 which is bigger than 0.8
so it is not included in the
loop.
As integers are always represented
correctly you may use the following
D1= 0.1 *
Optimize("D1",5,5,8,1);
Alternativelly you can use
this:
<FONT
size=2>D1=Optimize("D1",0.5,0.5,0.80001,0.1);
Anyway, I will try to implement some improvements
to workaround this problem
internally in AmiBroker.
Best regards,
Tomasz Janeczko
amibroker.com
<BLOCKQUOTE
>
----- Original Message -----
<DIV
>From:
Dimitris
Tsokakis
To: <A
href=""
title=amibroker@xxxxxxxxxxxxxxx>amibroker@xxxxxxxxxxxxxxx
Sent: Tuesday, November 06, 2001 9:16
AM
Subject: [amibroker] Optimization
Dear Tomasz,
I noticed that in
<FONT
size=2>D1=Optimize("D1",0.5,0.5,0.8,0.1);
the result list had
D1=0.5, 0.6, 0.7
In <FONT
size=2>D1=Optimize("D1",0.5,0.5,0.6,0.01);
the result was complete
D1=0.5, 0.51, 0.52, ..., 0.59, 0.60
Is there any reason for the first case?
Best Regards
Dimitris TsokakisYour use of Yahoo!
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