[R] Solving 100th order equation

[Peter Dalgaard]

Shubha Vishwanath Karanth wrote:
> To apply uniroot I don't even know the interval values... Does numerical methods help me? Or any other method?
>
> Thanks and Regards,
> Shubha
>
> -----Original Message-----
> From: Duncan Murdoch [mailto:murdoch at stats.uwo.ca] 
> Sent: Saturday, May 24, 2008 5:08 PM
> To: Shubha Vishwanath Karanth
> Subject: Re: [R] Solving 100th order equation
>
> Shubha Vishwanath Karanth wrote:
>   
>> Hi R,
>>
>>  
>>
>> I have a 100th order equation for which I need to solve the value for x. Is there a package to do this?
>>
>>  
>>
>> For example my equation is:
>>
>>  
>>
>> (x^100 )- (2*x^99) +(10*x^50)+.............. +(6*x ) = 4000
>>
>>  
>>
>> I have only one unknown value and that is x. How do I solve for this?
>>
>>   
>>     
> uniroot() will find one root.  If you want all of them, I don't know 
> what is available.
>
> Duncan Murdoch
>   
polyroot() is built for this, but it stops at 48th degree polynomials, 
at least as currently implemented. Not sure that it (or anything else) 
would be stable beyond that limit. YACAS perhaps?



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