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<FONT face=Arial
color=#0000ff size=2>Yes that's the difference between single precision (32 bit)
and double precision (64 bit) floating point numbers - memory. It also
takes up a fair bit more CPU time too. Not really a problem with the
3Ghz/1GB monster PCs we all have now though!
<FONT face=Arial
color=#0000ff size=2>
<FONT face=Arial
color=#0000ff size=2>The truncation you mention is not because the final digits
cannot be stored - it's because such numbers cannot be accurately stored into a
fixed bit size binary number representation. Indeed certain numbers cannot
be stored at all in binary format (such as numbers with recurring
sequences). It is possible to write optimisations to compensate for this
(eg. see what Microsoft has done).
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Best regards,
Richard Dale.
Norgate Investor Services- Premium
quality Stock, Futures and Foreign Exchange Data for markets in
Australia, Asia, Europe, UK & USA -<A
title=http://www.premiumdata.net/ href=""><FONT
face=Arial size=2>www.premiumdata.net
From: Daniel Kopti
[mailto:inspissated2003@xxxxxxxxx] Sent: Sunday, 28 March 2004 4:14
AMTo: equismetastock@xxxxxxxxxxxxxxxSubject:
[EquisMetaStock Group]
RE:_[EquisMetaStock_Group]_My_metastock_doesn4t_know_how_to_add
Although the hypertext documents in the message below would have you
believe that this is a hardware problem (nice try, Microsoft), it's
actually a software problem.
The programmers who designed MetaStock had to make some choices about the
kinds of data (integers, fractions, etc.) that the program would be
manipulating. They reasonably assumed that users would need access to
non-integers. So all numbers are assumed to have a decimal point, followed
by additional numbers (for example, an integer like 4 is treated as
4.0000). All of these numbers are expressed in scientific notation (as
explained in the hypertext documents), which can be easily converted to machine
language to be read by the computer hardware.
The issue is how much memory the program will allocate to each
number. The less memory, the faster the program runs and the less space it
occupies. However, larger numbers will be truncated, which results in loss
of data and errors in arithmetic. For example, a number like 14 969 161
could be saved as 14 969 160 (i.e. rounded down). Similarly, 14.969161
could be saved as 14.96916.
Unfortunately, the programmers who designed MetaStock did not allocate
enough memory to the numbers that the program is manipulating. In other
words, the program is truncating the numbers that you have specified, leading to
inaccurate results. That problem can only be corrected by the MetaStock
programmers.
--Daniel
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