Re: precision on all calcs

To: CALC-TI@LISTS.PPP.TI.COM
Subject: Re: precision on all calcs
From: Jeff Tyrrill <Jeff_Tyrrill@MSN.COM>
Date: Sun, 22 Jun 1997 20:06:04 UT
Reply-To: Jeff Tyrrill <Jeff_Tyrrill@MSN.COM>
Mathematically, 180*sin(1) does not equal pi. Although two mathematical
statements that have close, but slightly different, values can produce almost
the same answer in a floating point calculator. If the difference lies beyond
the 14 decimal places that the TI-8x can see, the TI-8x calculator will think
they are equal, but the TI-92, with its exact symbolic methods, will see the
difference.
________________

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-----Original Message-----
From:   Open discussion of TI Graphing Calculators  On Behalf Of Richard Bowman
Sent:   Sunday, June 22, 1997 8:36 AM
To:     CALC-TI@LISTS.PPP.TI.COM
Subject:        Re: precision on all calcs

Not perfect obviously (there isn't a perfect pi), but precise to the
decimals the calculator displays. (That is only 11 digits, which shouldn't
be too dificult)

BowmanSoft Software
http://www.bowmansoft.com/
Web Hosting and Design Services
 ----
From: Bernard Domroy <bdomroy@IEPSNET.COM>
To: CALC-TI@LISTS.PPP.TI.COM
Date: Sunday, June 22, 1997 11:28 AM
Subject: Re: precision on all calcs

>If you folks would pay attention in your math classes instead of playing
>these silly games, you would know the answer.  Pi is an irrational
number.
>Yet you would like a computer algorithm that returns an exact value for
the
>sin (1).  That's rich!!!
>
>At 23:57 6/21/97 UT, you wrote:
>>I just realized something. Even in degree mode, 180*sin(1) does not
exactly
>>equal pi. It differs in the ten-thousandth place, and if it were pi, the
>TI-92
>>would give that as an answer, but it doesn't. Oh well. I'll bet changing
to
>>degree mode solves his problem anyway.
>>________________
>>
>>Jeff Tyrrill's TI Calculator Site: Contains programming tips,
undocumented
>>discoveries and tips for power users, and comparisons of the different
>>calculator models.
>>http://tyrrill-ticalc.home.ml.org/
>>
>>TI-Files member: The premiere TI site on the web, with reviews of games
and
>>more.
>>http://ti-files.home.ml.org/
>>
>>
>>-----Original Message-----
>>From:   Jeff Tyrrill [SMTP:jeff_tyrrill@geocities.com]
>>Sent:   Saturday, June 21, 1997 4:51 PM
>>To:     CALC-TI@LISTS.PPP.TI.COM
>>Subject:        RE: precision on all calcs
>>
>>Change your calculator from the default radian mode to degree mode.
>>________________
>>
>>Jeff Tyrrill's TI Calculator Site: Contains programming tips,
undocumented
>>discoveries and tips for power users, and comparisons of the different
>>calculator models.
>>http://tyrrill-ticalc.home.ml.org/
>>
>>TI-Files member: The premiere TI site on the web, with reviews of games
and
>>more.
>>http://ti-files.home.ml.org/
>>
>>
>>-----Original Message-----
>>From:   Open discussion of TI Graphing Calculators  On Behalf Of
Boogeyman
>>Sent:   Saturday, June 21, 1997 1:12 PM
>>To:     CALC-TI@LISTS.PPP.TI.COM
>>Subject:        precision on all calcs
>>
>>When I make 180*sin1 on any of my calcs (80,82,92) I got something
weird,
>>but never pi. Does anybody know if it's the case with other calcs (I
only
>>go Ti's) ? (It also works with win calc, so I suppose somethin's wrong
in
>>all the OS.)
>>
>>TIA
>>
>>Boogeyman
>>
>