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Re: Low precision exponentiation

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  • Subject: [mg129842] Re: Low precision exponentiation
  • From: Tom Dickens <tomdickens at att.net>
  • Date: Mon, 18 Feb 2013 06:01:23 -0500 (EST)
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  • References: <kfq6mm$4v5$1@smc.vnet.net>

Use N[(25/10)^125,30] to get the high-precision answer.

= 5.52714787526044456024726519219*10^49


The input has to be specified to at least the desired precision.
Mathematica treats 2.5 as a machine-precision number.

Hope that helps,
Tom






On Sun, 17 Feb 2013 09:08:38 +0000 (UTC), Blaise F Egan
<blaise at blaisefegan.me.uk> wrote:

>I am trying to evaluate 2.5^125 to high precision. 
>
>R gives 5.527147875260445183346e+49 as the answer but Mathematica with N[2.5^125,30] gives 5.52715*10^49 and says that is to machine precision.
>
>I am inexperienced at Mathematica. Am I doing something silly?
>
>Blaise



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