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MathGroup Archive 2006

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Re: Real numerical computations

  • To: mathgroup at smc.vnet.net
  • Subject: [mg71785] Re: Real numerical computations
  • From: José Carlos Santos <jcsantos at fc.up.pt>
  • Date: Wed, 29 Nov 2006 02:56:26 -0500 (EST)
  • References: <ekeb6t$t42$1@smc.vnet.net> <ekh5n2$rp1$1@smc.vnet.net>

On 28-11-2006 11:14, Jean-Marc Gulliet wrote:

>> With Mathematica, if I type
>>
>> N[(-1.)^(1/3)]
>>
>> I get
>>
>> 0.5 + 0.866025 i
>>
>> This is correct, of course, but I would like to get -1. instead. How do
>> I tell Mathematica that I want a real result (if there is one)?
>>
> Have a look at the technical FAQ titled "How do I get x^(1/3) (where x 
> is a negative number) to evaluate to a real number?"
> 
> http://support.wolfram.com/mathematica/mathematics/algebra/realpower.html

Thanks. I didn't even knew about this FAQ!

Best regards,

Jose Carlos Santos


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