Re: implicit function
- To: mathgroup at smc.vnet.net
- Subject: [mg28322] Re: [mg28297] implicit function
- From: Tomas Garza <tgarza01 at prodigy.net.mx>
- Date: Wed, 11 Apr 2001 02:01:01 -0400 (EDT)
- References: <200104070744.DAA02036@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
The answer to FindRoot is in the form of a rule (see Help Browser under this
entry). Look at FullForm:
In[1]:=
FullForm[ff[0.5]]
Out[1]//FullForm=
List[Rule[y, 0.25`]]
You may then use
In[2]:=
ff[.5][[1, 2]]
Out[2]=
0.25
to get your answer the way you want it. Or, you may use ReplaceAll:
In[3]:=
y /. ff[0.5]
Out[3]=
0.25
If you wish to use the same symbol y for the root, you may write
In[4]:=
y = y /. ff[0.5]
Out[4]=
0.25
I know this is a real pain until you get used to it.
Tomas Garza
Mexico City
----- Original Message -----
From: "Phil Bonacich" <bonacich at soc.ucla.edu>
To: mathgroup at smc.vnet.net
Subject: [mg28322] [mg28297] implicit function
> This is a simple problem, but one that has bedeviled me. I define
> ff[x_] := FindRoot[2y == x, {y, .5}] . I don't want "{y -> 0.25}" when I
> enter ff[.5]; I want ".25", so that I can do other things with the
function
> ff. How do I get it?
>
>
- References:
- implicit function
- From: "Phil Bonacich" <bonacich@soc.ucla.edu>
- implicit function