Re: Polynomial to List
- To: mathgroup at smc.vnet.net
- Subject: [mg76916] Re: Polynomial to List
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Wed, 30 May 2007 05:13:53 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <f3grip$49r$1@smc.vnet.net>
Nick Hoffman wrote:
> I have a polynomial,
> Lets say:
>
> 1 + x + x^2 + x^3 + x^4
>
>
> and all I need to do is get that into a list of this form
>
> {x^4, x^3, x^2, x, 1}
>
> Any help would be greatly appreciated! Thanks!
The head of the expression poly is Plus. We replace it by List thanks to
the Apply function (short cut @@), then sort the resulting list to get
the desired form.
In[1]:=
poly = 1 + x + x^2 + x^3 + x^4;
Head[poly]
Reverse[List @@ poly]
Out[2]=
Plus
Out[3]=
{x^4, x^3, x^2, x, 1}
Regards,
Jean-Marc