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I made a function


that creates a random Polynomial of a certain degree, e.g.


now I want to create a Table of say 5 of those (different) Polynomials. A natural way would be

Table[makePolynomial, {5}]

but this creates 5 times the same Polynomial. How can I get a Table of 5 different Polynomials, that means makePolynomial is newly evaluated for each table item?

here is my makePolynomial function, I'm also looking for improvements:

makePolynomial[n_Integer, x_Symbol] := 
Module[{z, c}, z = RandomChoice[{-1, 1}] RandomInteger[{0, 100}];
c = Table[RandomInteger[{-100, 100}], {n}];
FromDigits[Reverse[AppendTo[c, z]], x]]
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You should show your definition of makePolynomial. Most likely you need SetDeleyed i.e. := insted of Set (=). E.g. makePolynomial[n_] := x^Range[0, n - 1].RandomInteger[{-10, 10}, n], then it works. –  Artes May 13 '13 at 11:42
Since your given code works as you desire it to, and the problem was something outside of the question asked, I am closing this as "too localized" as it is unlikely to be of use to anyone else. –  Mr.Wizard May 13 '13 at 12:41
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closed as too localized by Yves Klett, Artes, Mr.Wizard May 13 '13 at 12:42

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1 Answer

up vote 1 down vote accepted

I cannot give an explanation why it does not work for you unless you give the definition of your makePolynomial. But what about this?

makePolynomial[deg_] := Sum[RandomInteger[{0, 9}]*x^i, {i, 0, deg}]
Table[makePolynomial[3], {5}]
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Thanks, I found the problem. If I make f=makePolynomial and then Table[f,{5}] I get the same Polynomial 5 times. I obviously need to put the makePolynomial directly in the Table argument –  Martin Koller May 13 '13 at 11:46
@MartinKoller You need not putting it there directly if you use ` f := makePolynomial ` –  Artes May 13 '13 at 11:59
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