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The memory argument is getting a bit dated:
If you have 50000 bars for a security and load it all, it requires 100k
with single precision and 200k with double precision.
I'd trade precision for 100kb of RAM anytime! Even with 10 charts open,
we're only talking about 1 MB.
Secondly, floating point calculations are generally faster in double
precision than single precision.
Allan
--- PD Manager <pdmanager@xxxxxxxxxxxxxxxxx> wrote:
> At the risk of opening this can of worms again: you are correct in
> your
> assumption. All numbers in MetaStock are stored as single-precision
> floating point numbers. With this type of floating point
> representation,
> the computer only guarantees 7 digits of precision. When you have a
> number
> that exceeds this number of digits, any digits beyond the seventh are
> not
> guaranteed to be accurate. Any numbers that contain more digits than
> 7 are
> only approximations.
>
> To restate from past discussions on the subject: In the future, we
> could
> move to double precision numbers to get 15 digits of precision (any
> digits
> beyond the 15th would be inaccurate), but this would more than double
> the
> memory requirements of the program. The additional memory
> requirements of
> this approach is why the decision to make this change has not been
> made up
> to this point.
>
> Ken Hunt
> Programming Manager
> Equis International
>
>
> -----Original Message-----
> From: John R [mailto:jrdrp@xxxxxxxxxxxxxxxx]
> Sent: Wednesday, May 02, 2001 3:52 PM
> To: metastock@xxxxxxxxxxxxx
> Subject: Re: Current Day!
>
>
> I would guess this problem is caused by the underlying floating point
> representation MS probably uses for numeric variables. i.e. losing
> accuracy
> at the extreme limits of range.
>
> Instead of using full century why not try using just 2 digits i.e.
> 00, 01,
> 99. Or if year collating order is reqd. 3 digits i.e. 098 (for 1998)
> 099
> (for 1999) 100 (for 2000) 101 (for 2001) etc.
>
> Haven't checked any of this!
>
> John
>
>
> ----- Original Message -----
> From: "C.S." <csaxe@xxxxxxxxxxx>
> To: <metastock@xxxxxxxxxxxxx>
> Sent: Wednesday, May 02, 2001 8:38 PM
> Subject: Re: Current Day!
>
>
> I tried the equation backwards to see if DDMMYYYY would work.
>
> DOM:=DayOfMonth();
> MON:=Month();
> YR:=Year();
> YR+(MON*10000)+(DOM*1000000)
>
> It works for the first day but not for the days at the end of the
> month.
> for 4/30/2001 I get 30042000 and not 30042001.
>
> -Corey
> ----- Original Message -----
> From: Steve Brann
> To: metastock@xxxxxxxxxxxxx
> Sent: Wednesday, May 02, 2001 9:36 AM
> Subject: RE: Current Day!
>
>
> Hi L
>
> Thanks. Version 7.02 end of day version.
>
> I am also getting results such as 20001032 (Oct 32nd, 2000) when I
> should
> be getting 20001101 (Nov 1st,2000). Interesting eh?
>
> Steve
> -----Original Message-----
> From: owner-metastock@xxxxxxxxxxxxx
> [mailto:owner-metastock@xxxxxxxxxxxxx]On Behalf Of Lionel Issen
> Sent: 02 May 2001 14:52
> To: metastock@xxxxxxxxxxxxx
> Subject: Re: Current Day!
>
>
> Steve:
> This is an excellent concise method.
>
> What version are you using?
>
> Lionel Issen
> lissen@xxxxxxxxx
> ----- Original Message -----
> From: Steve Brann
> To: metastock@xxxxxxxxxxxxx
> Sent: Wednesday, May 02, 2001 7:05 AM
> Subject: Current Day!
>
>
> Hi
>
> I use the following in my explorations to denote the date of
> the last
> price data in the format yyyymmdd;
>
> DayOfMonth()+(Month()*100)+(Year()*10000)
>
> However, this fails if the date is the first of the month such
> as
> March 1st 2001, instead of getting 20010301 I get 20010300!
>
> Has anyone else experienced this and if so is there a solution?
> By
> the way, using DayOfMonth() on its own produces 01.
>
> Thanks in advance
>
> Steve
>
=====
---
Allan Havemose, Ph.D.
havemose@xxxxxxxxxx
havemose@xxxxxxxxx
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