Re: Low precision exponentiation
- To: mathgroup at smc.vnet.net
- Subject: [mg129850] Re: Low precision exponentiation
- From: Bob Hanlon <hanlonr357 at gmail.com>
- Date: Mon, 18 Feb 2013 06:04:03 -0500 (EST)
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- References: <20130217090833.8CF776937@smc.vnet.net>
To avoid using machine precision enter exact numbers (Rationalize). Exact result: Rationalize[2.5]^125 2350988701644575015937473074444491355637331113544175043017503412556834518909454345703125/42535295865117307932921825928971026432 To a specified precision N[%, 25] 5.527147875260444560247265192192255725514240233239`25.*^49 Bob Hanlon On Sun, Feb 17, 2013 at 4:08 AM, 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 >
- References:
- Low precision exponentiation
- From: Blaise F Egan <blaise@blaisefegan.me.uk>
- Low precision exponentiation