Can Plot, can't FindRoot - what gives?
- To: mathgroup at smc.vnet.net
- Subject: [mg97718] Can Plot, can't FindRoot - what gives?
- From: Aaron Fude <aaronfude at gmail.com>
- Date: Thu, 19 Mar 2009 02:13:37 -0500 (EST)
Hi,
Here's my code for a model problem. I do not need a solution to this
simple problem, of course - I just need to understand why Mathematica
is giving me an error.
f[c_] := (
s = NDSolve[{ y'[x] == c - 1, y[0] == 0}, y, {x, 0, 2*Pi}];
(Evaluate[y[x] /. s] /. x -> 2*Pi)[[1]]
)
Plot[f[c], {c, 0, 10}]
f[1]
FindRoot[f[c] == 0, {c, 1}]
I get a series of errors, the first of which is
NDSolve::ndnum: Encountered non-numerical value for a derivative at x
\== 0.`
I'm on Win32 version 6.
Many thanks in advance,
Aaron