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Re: FindRoot, suppressing complex interval-numbers


$Version
5.1 for Microsoft Windows (October 25, 2004)

Hi Paul,
can't see any complex numbers from
 > FindRoot[Sin[x] +2, {x, 1.656 10^8, 1.653 10^8, 1.658 10^8},
 > EvaluationMonitor :> AppendTo[xs, x]]
Are you fooling yourself?
Daniel

Paul wrote:
> Hello,
> I have the following problem:
> Take the simple example
> 
> FindRoot[Sin[x] +2, {x, 1.656 10^8, 1.653 10^8, 1.658 10^8},
> EvaluationMonitor :> AppendTo[xs, x]]
> 
> In the Help we can read: "FindRoot[lhs==rhs, {x, a, a_min, a_max}]
> searches for a solution, stopping the search if x ever gets outside the
> range a_min to a_max. "
> 
> But when I display xs I can see, that there are also two complex
> numbers used.
> 
> This is a problem if I use a function (in my case a compiled one)
> inside FindRoot, which only accepts real numbers.
> 
> So how can I suppress the using of complex numbers in FindRoot?
> 
> Best regards,
> Paul
> 
> (Mathematica 5.2)
> 


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