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6 Nov 2024 02:24:33 EST (-0500)
  Double precision (Message 1 to 5 of 5)  
From: Orchid XP v8
Subject: Double precision
Date: 24 Aug 2008 08:21:28
Message: <48b15248$1@news.povray.org>
Unfortunately Wikipedia doesn't seem to have much to say about double 
precision floating point arithmetic. Can anybody tell me what the 
smallest (positive) number you can "reliably" take the reciprocol of is? 
("Reliably" as in "with some degree of numerical precision".)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Chambers
Subject: Re: Double precision
Date: 24 Aug 2008 13:03:24
Message: <48b1945c@news.povray.org>
Orchid XP v8 wrote:
> Unfortunately Wikipedia doesn't seem to have much to say about double 
> precision floating point arithmetic. Can anybody tell me what the 
> smallest (positive) number you can "reliably" take the reciprocol of is? 
> ("Reliably" as in "with some degree of numerical precision".)
> 

2^-1022, I believe.  This is the smallest positive number that can be 
represented by a double.

...Chambers


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From: Orchid XP v8
Subject: Re: Double precision
Date: 24 Aug 2008 13:25:29
Message: <48b19989@news.povray.org>
Chambers wrote:
> Orchid XP v8 wrote:
>> Unfortunately Wikipedia doesn't seem to have much to say about double 
>> precision floating point arithmetic. Can anybody tell me what the 
>> smallest (positive) number you can "reliably" take the reciprocol of 
>> is? ("Reliably" as in "with some degree of numerical precision".)
>>
> 
> 2^-1022, I believe.  This is the smallest positive number that can be 
> represented by a double.

Is that a normal or a denormal? (If I'm understanding this correctly, 
denormals are less precise.)

Also, I guess the reciprocol of that ought to be 2^1022. Is that also 
within range?

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Chambers
Subject: Re: Double precision
Date: 24 Aug 2008 15:15:29
Message: <48b1b351$1@news.povray.org>
Orchid XP v8 wrote:
> Chambers wrote:
>> 2^-1022, I believe.  This is the smallest positive number that can be 
>> represented by a double.
> 
> Is that a normal or a denormal? (If I'm understanding this correctly, 
> denormals are less precise.)

No clue, I'm not familiar with denormal numbers.

> Also, I guess the reciprocol of that ought to be 2^1022. Is that also 
> within range?

Yes, the range for the exponent is -1022 through 1023.

...Chambers


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From: somebody
Subject: Re: Double precision
Date: 24 Aug 2008 22:52:24
Message: <48b21e68@news.povray.org>
"Orchid XP v8" <voi### [at] devnull> wrote in message
news:48b15248$1@news.povray.org...

> Unfortunately Wikipedia doesn't seem to have much to say about double
> precision floating point arithmetic.

This one does:

http://docs.sun.com/source/806-3568/ncg_goldberg.html


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