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Re: Can't get Mathematica to evaluate correctly a

  • To: mathgroup at smc.vnet.net
  • Subject: [mg111545] Re: Can't get Mathematica to evaluate correctly a
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Wed, 4 Aug 2010 07:39:58 -0400 (EDT)
  • Reply-to: hanlonr at cox.net

The input expression must have higher precision

N[173746*Sin[10^22] +
  94228*Log[171/10] -
  78487*Exp[42/100], 10]

-1.341818958*10^-12

N[Release[Rationalize[Hold[
    173746*Sin[10^22] +
     94228*Log[17.1] -
     78487*Exp[0.42]]]], 10]

-1.341818958*10^-12


Bob Hanlon

---- Damien Wyart <damien.wyart at free.fr> wrote: 

=============
Hello,

I am using Mathematica 7.0.2 and playing a bit with an expression
analyzed in the following paper:
http://www.loria.fr/~zimmerma/papers/cise.pdf

I tried many constructions with N and SetPrecision and can't get
Mathematica to output the correct result (I am not very experienced with
Mathematica). Here is the expression :

173746*Sin[10^22]+94228*Log[17.1]-78487*Exp[0.42]

The correct result should be -1.341818958*10^-12 but even forcing each
term with N and a very large number, I am still not getting this value
at all.


Any help will be appreciated. Thanks in advance ; best regards,

-- 
Damien Wyart




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