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Is there a way to find all roots of a polynomial equation in R?

6 messages · Duncan Murdoch, Rolf Turner, JesperHybel +2 more

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On 12-04-18 4:14 PM, Michael wrote:
polyroot() should be able to do it, assuming that a,b,c,d and e are 
numeric or complex values, not just symbols.

Duncan Murdoch
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On 19/04/12 08:14, Michael wrote:
I believe that Galois (or maybe it was Abel) proved that this
is *NOT* possible, a couple of centuries ago.

However if you are thinking of *numerical* methods (i.e. supplying
numerical values for a, b, ..., e before you start) then polyroot()
will do it for you.  As

     RSiteSearch("zeroes of polynomial")

would have told you.  (Seventh hit.)

     cheers,

         Rolf Turner
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The package rootSolve might proove interesting
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not much to speak of.
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Michael <comtech.usa at gmail.com> wrote: