Re: Problem: is not a list of numbers with dimensions
- To: mathgroup at smc.vnet.net
- Subject: [mg88494] Re: Problem: is not a list of numbers with dimensions
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Tue, 6 May 2008 06:44:48 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <fvmn0l$8j1$1@smc.vnet.net>
Fikri Serdar GOKHAN 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; ==========^^^ Must be Exp > FindRoot[x-A*exp[k*g*x*Leff-Attenuation*L],{x,0}] ===============^^^ Must be Exp > 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 ============^^^ Must be Exp Hi Serdar, You just made a typo when writing the exponential function. Keep in mind that every function names starts with a capital letter, i.e. *Exp* and not exp. In[1]:= 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}] Out[7]= {x -> 0.0000454986} Regards, -- Jean-Marc