24 Feb
2003
24 Feb
'03
4:13 a.m.
A real computer doesn't know what the square root of negative one is? :-P
-----Original Message-----
From: Fred Cisin (XenoSoft) [mailto:cisin@xenosoft.com]
Sent: Saturday, February 22, 2003 1:33 PM
To: cctalk(a)classiccmp.org
Subject: Re: Trivia Question
On Sat, 22 Feb 2003, Hans B Pufal wrote:
It significantly enhances its reality coefficient.
But a REAL computer has casters, (or a forklift)
A REAL computer dims the lights during power-up (for the NEIGHBORHOOD)
A REAL computer attracts attention from the Fatherland Security.
If I write a
PC emulator that runs on a real computer, does the computer
become not real?
Or does my PDP-9 emulator running on my PC make IT 'a real
computer'. I 
24 Feb
24 Feb
4:31 a.m.
New subject: The REAL definition of "REAL" (was: Trivia Question
On Mon, 24 Feb 2003, Feldman, Robert wrote:
A real computer doesn't know what the square root
of negative one is? :-P
Thank you.
Last week, I was explaining to one of my classes the differences between
Floating Point and Real.
A REAL computer (if there were such - analog??) would have infinite
numbers between 1 and 2. A Floating Point system only has about 8
million, and doesn't have any odd numbers above about 16 million.
Double precision has substantially more, but still quite clearly
finite.
5:03 a.m.
New subject: The REAL definition of "REAL" (was: Trivia Question
Fred Cisin (XenoSoft) wrote:
On Mon, 24 Feb 2003, Feldman, Robert wrote:
Does odd/even have much meaning with floating point numbers,
real or otherwise?
Being even means it can be divided by two without any remainder,
but with any king of floating point, remainder doesn't have much
meaning. ie. is 3.4 or 3.5 odd or even? What are the reaminders?
Is PI odd or even?
The only way to decide is to convert them to integers, and then
decide, but then you are working with a different set of numbers.
A real computer doesn't know what the square
root of negative one is? :-P
Thank you.
Last week, I was explaining to one of my classes the differences between
Floating Point and Real.
A REAL computer (if there were such - analog??) would have infinite
numbers between 1 and 2. A Floating Point system only has about 8
million, and doesn't have any odd numbers above about 16 million.
Double precision has substantially more, but still
quite clearly
finite.
6:33 a.m.
New subject: The REAL definition of "REAL" (was: Trivia Question
>numbers between 1 and 2. A Floating Point system
only has about 8
>million, and doesn't have any odd numbers above about 16 million.
On Mon, 24 Feb 2003, Kevin Handy wrote:
Does odd/even have much meaning with floating point
numbers,
real or otherwise?
Yes, it DOES.
The point is that with floating point numbers, there are GAPS. BIG
gaps. Try storing a value of 100,000,001.0 in floating point.
You can't.
If you store 2147483649.0 in float, it will store 2147483648.0
[IEEE float, not any customized or imaginary system]
Being even means it can be divided by two without any
remainder,
OR having a remainder of 0.0
but with any king of floating point, remainder
doesn't have much
meaning. ie. is 3.4 or 3.5 odd or even? What are the reaminders?
odd, odd, 1.4,
1.5
Is PI odd or even?
odd
but 4.0 is considered to be EVEN.
The only way to decide is to convert them to integers,
and then
decide, but then you are working with a different set of numbers.
NOPE.
While it is, admittedly, an integer concept, any integer multiple of 2.0
(remainder of 0.0) is considered to be an even number.
AND THE RELEVANT part is that NO number over 16M that is not an integer
multiple of 2.0 can be stored in floating point! Past 8M, there are no
floating point numbers that are not exactly equal to integers.
5:06 a.m.
New subject: The REAL definition of "REAL" (was: Trivia Question
No there is no REAL computer. An "analog" computer is
really digital, the resolution is a function of the
charge on an electron and the supply voltage used in a
particular application.
steve
--- "Fred Cisin (XenoSoft)" <cisin(a)xenosoft.com>
wrote:
On Mon, 24 Feb 2003, Feldman, Robert wrote:
A real computer doesn't know what the square
root
of negative one is? :-P
Thank you.
Last week, I was explaining to one of my classes the
differences between
Floating Point and Real.
A REAL computer (if there were such - analog??)
would have infinite
numbers between 1 and 2. A Floating Point system
only has about 8
million, and doesn't have any odd numbers above
about 16 million.
Double precision has substantially more, but still
quite clearly
finite.
7925
days inactive
7925
days old
4 comments
4 participants
participants (4)
-
cisin＠xenosoft.com -
gkicomputers＠yahoo.com -
kth＠srv.net -
Robert_Feldman＠jdedwards.com