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Re: Low precision exponentiation

• To: mathgroup at smc.vnet.net
• Subject: [mg129841] Re: Low precision exponentiation
• From: Sseziwa Mukasa <mukasa at gmail.com>
• Date: Mon, 18 Feb 2013 06:01:03 -0500 (EST)
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• References: <20130217090833.8CF776937@smc.vnet.net>

Mathematica interprets numbers entered as decimals as machine precision.
 The easiest but not only way to get a high precision answer to your
problem is to enter a rational: N[(5/2)^125,30].

Regards,
Sseziwa

On Sunday, February 17, 2013, Blaise F Egan 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
>
>

• References:
  • Low precision exponentiation
    • From: Blaise F Egan <blaise@blaisefegan.me.uk>