[Jprogramming] using ^ and ^.

[butch.lakeshsore at antelecom.net]

I never thought about the print percision.

This with the previous post by Raul should get me going.

Alsothanks for  the post about model of Tolerant Equal found
at:

http://www.jsoftware.com/jwiki/Essays/Tolerant%20Comparison

cut/past from this page follows:

----------------------

The = dictionary page defines equality with a tolerance t
thus: for finite x and y , x=y  is 1 if the magnitude of x-y
does not exceed t times the larger of the magnitudes of x
and y .

The tolerance is normally 2^_44 . Appendix C, System
Conventions and Limits, says that the tolerance is less than
or equal to 2^_34 . Historically, the upper bound on the
tolerance was chosen so that comparisons involving 32-bit
integers are exact (as if the tolerance is 0). 

----------------------

thanks a lot!

----- Original Message Follows -----
From: Kip Murray <km at math.uh.edu>
To: Programming forum <programming at jsoftware.com>
Subject: Re: [Jprogramming] using ^ and ^.
Date: Mon, 15 Jun 2009 12:27:28 -0500

>    9!:11 [ 20  NB. Print precision 20
>
>    2x ^. 2x ^ 47
>47.000000000000007
>
>
>butch.lakeshsore at antelecom.net wrote:
>>     2x ^. 2x ^ 607
>> 607
>> 
>> and even though it takes about 10 seconds on my machine.
>> 
>>    2x ^. 2x ^ 444444                                     
>>                                                          
>> 444444
>> 
>> ^. and ^ do not seem to be a problem.
>> 
>> ----- Original Message Follows -----
>> From: Raul Miller <rauldmiller at gmail.com>
>> To: Programming forum <programming at jsoftware.com>
>> Subject: Re: [Jprogramming] question on using ^ and ^.
>> Date: Mon, 15 Jun 2009 12:15:57 -0400
>> 
>>> On Mon, Jun 15, 2009 at 12:06 PM,
>>>> <butch.lakeshsore at antelecom.net> wrote: Hum.... more
>>>> observations: 
>>>>   (-:!.0 <.) 2x ^.  2x^47
>>>> 0
>>>   (- <.) 2x ^.  2x^47
>>> 7.10543e_15
>>>
>>> The issue, I think, is the implementation
>>> of ^. not recognizing an exact integer
>>> result was possible.
>>>
>>> -- 
>>> Raul
>>>
>>>
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