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I'm new to Mathematica. I need to generate a list of 1000 triplets of random numbers {r, p, t}, so that 0 < r < 1, 0 < p < 2 π and 1 < t < 10, with t being an integer.

I've found the two functions RandomReal and ``RandomInteger`, but can't seem to obtain what I need -- namely not a list.

I need to pass this list of triplets to a function f[r_, p_, t_].

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    $\begingroup$ list=Transpose@{RandomReal[{0,1},1000],RandomReal[{0,2 Pi},1000], RandomInteger[{1,10},1000]} is the most straight forward. Then you can do f@@@list $\endgroup$
    – N.J.Evans
    Jul 22, 2016 at 20:27
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    $\begingroup$ From what distributions are you sampling? Do you just want uniform samples chosen? In that case, use @N.J.Evans's solution. Otherwise, please be more specific. $\endgroup$
    – march
    Jul 22, 2016 at 20:43
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    $\begingroup$ Regarding N.J.Evans's comment, @@@ is shorthand for Apply with a levelspec of {1}; see the documentation for Apply for more information. $\endgroup$
    – Mr.Wizard
    Jul 22, 2016 at 21:44

1 Answer 1

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For the sake of demonstration, let us suppose

f[r_Real, p_Real, t_Integer] := r Sin[p t]

With[{n = 10}, 
  triples = 
    Transpose[
      {RandomReal[{0, 1}, n], 
       RandomReal[{0, 2 Pi}, n], 
       RandomInteger[{1, 10}, n]}]];

Note that this last definition can generate a list of triples of any size by changing the value given to n.

Now, N. J. Evans' answer is the most straight forward.

f @@@ triples

{0.273082, 0.603514, -0.296061, 0.09708, 0.174089, -0.255095, 0.173383, 0.304217, 0.170979, 0.160158}

However, because Mathematica can apply it powerful pattern matcher to arguments, you can also do this

ff[{r_, p_, t_}] := f[r, p, t]
ff /@ triples

or even this.

fff[triples : {{_, _, _} ..}] := f @@@ triples
fff[triples]
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