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I have a question. I want to write the result of the expression such as y=2cos(n.Pi/3) for 100 values n into a list. Could you tell me which code I should use?

J. M.'s missing motivation
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Vô Danh
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3 Answers3

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As @LouisB comments, using Table:

f[n_] := 2 Cos[n π/3]
Table[f[n], {n, 1, 100}]

({1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, 
  -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1,

  -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2,

  -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 
   2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1, -1, -2, -1, 1, 2, 1,-1, -2, -1})
E. Chan-López
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    https://mathematica.stackexchange.com/questions/269646/table-mix-with-if-function Could you explain to me this question? – Vô Danh Jun 19 '22 at 12:21
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You can take advantage of the Listable attribute of the trigonometric functions (ie the fact that they automatically thread over lists, to produce a list of results) as follows:

2 Cos[Pi/3 Range@100]
MarcoB
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Andreas Lauschke
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  • https://mathematica.stackexchange.com/questions/269646/table-mix-with-if-function Could you explain to me this question? – Vô Danh Jun 19 '22 at 12:21
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Using Array :

Array[2 Cos[# \[Pi]/3] &, 100]

also delivers the same output. If you don't want to use pure functions or if a function is available, then you can use the function (as given in the other answer).

f[n_] := 2 Cos[n π/3]
Array[f, 100]
Syed
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