Re: Creation and evaluation of polynomials
- To: mathgroup at smc.vnet.net
- Subject: [mg89475] Re: [mg89436] Creation and evaluation of polynomials
- From: "Szabolcs HorvÃt" <szhorvat at gmail.com>
- Date: Tue, 10 Jun 2008 03:43:13 -0400 (EDT)
- References: <200806091019.GAA05076@smc.vnet.net>
On Mon, Jun 9, 2008 at 13:19, <jmgomezgoo at gmail.com> wrote:
> Hi!
>
> Image we have a function that create a Polynomial:
>
> polynomial[{1,0,0,0,1,0,1,}] -> p^5 + 3p^2
>
> And we want to calulate roots and the derivate of this polynomial.
>
> I try with ToString[polynomial[{1,0,0,0,1,0,1}]] in order to use
> convert the polynomial expression to string first and later use
>
> ToExpression[]
>
> and calculate roots
>
> D[ToExpression[ToString[polynomial[{1,0,0,0,1,0,1}]], x]
>
> like the next examples:
>
> D[ToExpression["x^2+2x"], x]
>
> or
>
> NSolve[ToExpression["x^2+2x==x"], x]
>
>
> But ToString erase ^ symbol.
>
> Somebody knows how to solve it?
>
I don't see any reason for converting to a string and then back. Why
do you want to do that?
The answer: ToString[x^2, InputForm]
- References:
- Creation and evaluation of polynomials
- From: jmgomezgoo@gmail.com
- Creation and evaluation of polynomials