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Re: Interesting problem looking for a solution.

  • To: mathgroup at smc.vnet.net
  • Subject: [mg122049] Re: Interesting problem looking for a solution.
  • From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
  • Date: Tue, 11 Oct 2011 04:22:13 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com

Hi, Gary,

The answer may be pretty simple depending upon what precisely you have in mind. Say, how many students do you expect to have and what type of functions do you want to give them. You do not specify it in your question. Below I propose a simple example, for the case you will be satisfied with polynomials.

You may also think about trigonometric polynomials, or combination of algebraic and trigonometric, you may think about exponential functions or Bessel's functions and so on.



(* Here a list of quasi-random polynomial is defined. Parameter "numberOfStudents" defines the total number of polymers in the list. Parameter "coeffLimits" defines limits in which its coefficients will vary, the parameter "order " defines the polynomial  order  *)



functionsList[numberOfStudents_,coeffLimits_,order_]:=Table[Table[RandomInteger[{-coeffLimits,coeffLimits}]*x^i,{i,0, order }]/.List->Plus,{numberOfStudents}]



(*  Here are 10 such polynomials of the fourth order, with coefficients between -5 and 5   *)



lst=functionsList[10,5,4]



{5+5 x^2+4 x^3+4 x^4,-4+2 x-2 x^2-x^4,-4-5 x-5 x^2-x^3-5 x^4,2+x+5 x^2-x^3+2 x^4,5+2 x-2 x^2-x^3-4 x^4,-5+x-2 x^2-4 x^3+4 x^4,-5+2 x+3 x^2+5 x^3+x^4,3-2 x-3 x^2-5 x^3-3 x^4,1-4 x-2 x^2-x^4,-1+3 x+5 x^2-4 x^3-2 x^4}



(* Here they are plotted *)

Plot[lst,{x,-2,2}]

Alexei BOULBITCH, Dr., habil.

IEE S.A.

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e-mail: alexei.boulbitch at iee.lu<mailto:alexei.boulbitch at iee.lu>



Hello,



I have an (I think) interesting problem for you Mathematica gurus.



I'm trying to create a worksheet for my students and want to be able to display the plot of a randomly generated function f[x], without them being able to access the expression which defines f; In other words, I don't want them to be able to evaluate f[x].



The idea is that each student will get a different function f[x] and will see a different graph and they have to determine the expression which defines f. They then have to plot the function they think is f against the actual function f[x] and turn in the two plots (or the one plot with the two graphs.)



Is this possible?



Thanks much,

Gary





From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
Subject: [mg122049] Re: Interesting problem looking for a solution.
To: mathgroup at smc.vnet.net




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