Re: Why won't Horner[] work?
- To: mathgroup at smc.vnet.net
 - Subject: [mg59037] Re: Why won't Horner[] work?
 - From: "Lalu" <BhuvaneshBhatt at gmail.com>
 - Date: Wed, 27 Jul 2005 01:25:21 -0400 (EDT)
 - References: <dc4r39$i9$1@smc.vnet.net>
 - Sender: owner-wri-mathgroup at wolfram.com
 
Hi Paul,
> When I issue the command:
>
> In:= Fit[ {{1,200},{200,0},{400,200}}, {1,x,x^2}, x]
>
> Out:= 202.01 - 2.01508 x + 0.00502513 x^2
>
> This seems good.  But when I do
>
>
> In:= Horner[Fit[ {{1,200},{200,0},{400,200}}, {1,x,x^2}, x]]
>
> Out:= Horner[202.01 - 2.01508 x + 0.00502513 x^2]
>
>
> Why doesn't it evaluate the polynomial?  To I need to convert the
> output of fit?
Fit is a kernel function, while you need to load the Algebra` package
to use the Horner function:
In[1]:= <<Algebra`Horner`
In[2]:= Horner[Fit[{{1,200}, {200,0}, {400,200}}, {1, x, x^2}, x]]
Out[2]= 202.01 + (-2.01508 + 0.00502513 x) x
Bhuvanesh,
Wolfram Research.