Question about FindRoot function?

*To*: mathgroup at christensen.cybernetics.net*Subject*: [mg1244] Question about FindRoot function?*From*: ptaszyns at uci.agh.edu.pl (Boguslaw Ptaszynski)*Date*: Fri, 26 May 1995 06:10:11 -0400*Organization*: University of Mining & Metallurgy

Hi, MathGroup ! I have a problem with FindRoot function. I want to find some roots of any one variable function ff[x], when x runs from x1 to x2 and uses step dx. I have written the Package named zerowe.m : BeginPackage["Zerowe1`"] Zerowe1::usage=".." Begin["`Private`"] Zerowe1[ ff_,pe_,x1_,x2_,dx_] := Module [ {pierw,imax,u,k,llk,i}, pierw=Table[FindRoot[ff==0,{x,k},AccuracyGoal->10, MaxIterations->50,WorkingPrecision->30],{k,x1,x2,dx}]; imax=Length[pierw]; ] End[] EndPackage[] Next, I have started the procedure: <<Private/zerowe1.m Zerowe[Tan[x]+(2/pe)*x, 60, 2, 20, 0.5] and I have got the following message: FindRoot::frnum: Function(Tan[x]+(2/pe)*x)is not a length 1 list of numbers at (Zerowa1`Private`x)=(2.0) FindRoot::frns: Starting value Zerowe1`Private`k$1 in (Zerowe1`Private`x,Zerowe1`Private`k$1) is not a number and Out: {{Zerowe1`Private`x,Zerowe1`Private`k$5}} Can someone tell me how does this problem solve ? Many thanks, Regards, Boguslaw Ptaszynski