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what does the function min() do???

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Old   November 9, 2009, 20:54
Default what does the function min() do???
Sven Winkler
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Somewhere in the source Code of a turbulence model I found something which I dont understand. Unfortunately the understanding of this line is crucial to what I am doing. The line I am talking about is

P[faceCelli] *=
                    min(G[faceCelli]/(0.5*mag(tr(P[faceCelli])) + SMALL), 1.0);
What I dont understand are the following things:

  • what is SMALL? A variable a function??
  • what does the function min do? Does it select eitherG[faceCelli]/(0.5*mag(tr(P[faceCelli])) + SMALL) or 1.0, depending on which value is the smaller one
If I do some more source Code searching, I find

inline retType min(const type1 s1, const type2 s2) \
{                                                  \
    return (s1 < s2)? s1: s2;                      \
Can someone understand this?

Thank you very much!
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Old   November 9, 2009, 22:41
Simon Lapointe
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min(a,b) returns the smallest value between a and b. SMALL stands for a small finite value, in this case it is used to avoid a possible division by 0.
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