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> -----Message d'origine-----
> De : Bob Fulks [mailto:bfulks@xxxxxxxxxxxx]
> Envoye : dimanche 22 juillet 2001 20:03
>.
>
> Pierre:
>
> The way I read Kent's post he is exactly correct so I conclude that
> he understands how floating point works.
>
Are you kidding?
The number of signifiant digits in FP is no more than 10 ( depends on
various sources), and what I read was an example waiting for a 22 digits
precision by ading two Float, means a perfect misunderstanding!
Here is an example from the web
http://www.google.com/search?q=cache:Wx1TpZPpalo:www.developpez.com/sgbd/ODI
BDataType.htm+Float+precision+nombre&hl=fr&lr=lang_fr
DECIMAL(precision,scale)
variable
precision = 1 a 15 (digits) et scale 1 a 15 (decimals incluses)
Exemple : DECIMAL(10,3) autorisera un nombre de type ppppppp.sss
DOUBLE PRECISION
64 bits
1.7x10-308 a 1.7x10308
notation scientifique, 15 digits de precision
FLOAT
32 bits
3.4x10-38 a 3.4x1038
simple precision, 7 digits
NUMERIC(precision,scale)
variable
precision = 1 a 15 (digits) et scale 1 a 15 (decimals incluses)
Idem DECIMAL
INTEGER
32 bits
-2.147.483.648 a 2.147.483.647
entier long signe
SMALLINT
16 bits
-32 768 a 32 767
entier court signe
> The way I read your post of 7/19/01 suggesting the following code:
>
> >if sum> = 9999999- 2*price
> >{ please check the acceptable precision limit according to your own TS
> >precision belief}
> >then begin
>
> makes me think that you do not understand how floating point works.
The 9999999 7 digitslimit has been set beyond the FP limit to avoid the TS
problem overflow where the precision may be lost after a given high limit.
As anyone disagree on what is the true TS variable precision, I have set
this " according to your own belief" in my comment.
Please conduct further testing if yoy want to determine what is the highest
number in EL not affected by cumulative overflow, I have other things to do.
The only reproach that yoiu can do is thta I gave the example for a
positive accumulation ( whre in this case you may use the absvalue.
>
> So, based upon these post, I would think you are the one who needs to
> do some reading...
Bad thinking , dear Bob.
Sincerely,
Pierre Orphelin
www.sirtrade.com
TradeStation Technologies representative in France
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