Re: Problem: is not a list of numbers with dimensions
- To: mathgroup at smc.vnet.net
- Subject: [mg88507] Re: [mg88450] Problem: is not a list of numbers with dimensions
- From: "W_Craig Carter" <ccarter at mit.edu>
- Date: Tue, 6 May 2008 06:47:12 -0400 (EDT)
- References: <200805051016.GAA08633@smc.vnet.net>
Hello Fikri,
When beginning to use Mathematica, it is probably a good idea to leave
off the trailing ";"
In this way, you will quickly see the syntax errors---this will lead
you to start exploring some of the documentation. For this example, I
would say this would be a good paradigm for those just getting
started:
(*Build up expressions with symbols, not numbers*)
Leff = (1 - Exp[-Attenuation*L])/Attenuation
GenExpr = x - A*Exp[k*g*x*Leff - Attenuation*L]
(*use replace to create a particular instance of your expression*)
Expr = GenExpr /. {A -> 10^(-4), k -> 2/3, g -> 1.12*10^(-11),
L -> 7200, Attenuation -> 0.23026*0.475*10^(-3) }
(*visualize what you intend to do*)
Plot[Expr, {x, -1, 1}]
(*Check the documentation and (if everything is fine) get your answer*)
FindRoot[Expr, {x, 0}]
On Mon, May 5, 2008 at 6:16 AM, Fikri Serdar GOKHAN <fsgokhan at gmail.com> wrote:
> When run the below code,
>
>
> A=1*10^(-4);
>
> k=2/3;
>
> g=1.12*10^(-11);
>
> Attenuation= 0.23026*0.475*10^(-3);
>
> L=7200;
>
> Leff=(1-exp[-Attenuation*L])/Attenuation;
>
>
>
> FindRoot[x-A*exp[k*g*x*Leff-Attenuation*L],{x,0}]
>
>
>
> It executes the below solution,
>
>
>
> FindRoot::nlnum: The function value {0.-0.0001 exp[-0.787489+0. \
>
> (1.+Times[<<2>>])]} is not a list of numbers with dimensions {1} at \
>
> {x} = {0.}.
>
>
>
> I need your help about numerical and Alpha_numeric solution of this problem.
>
>
>
>
> f(x)= x-A*exp[k*g*x*Leff-Attenuation*L
>
>
>
> Serdar
>
>
>
--
W. Craig Carter
- References:
- Problem: is not a list of numbers with dimensions
- From: "Fikri Serdar GOKHAN" <fsgokhan@gmail.com>
- Problem: is not a list of numbers with dimensions