Factorial.h

//===========================================================================
// GoTools - SINTEF Geometry Tools version 1.1
//
// GoTools module: CORE
//
// Copyright (C) 2000-2007 SINTEF ICT, Applied Mathematics, Norway.
//
// This program is free software; you can redistribute it and/or          
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// as published by the Free Software Foundation version 2 of the License. 
//
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//===========================================================================
#ifndef _FACTORIAL_H
#define _FACTORIAL_H


namespace Go {





template<int N>
struct Factorial {
    enum { value = N * Factorial<N-1>::value };
};


template <>
struct Factorial<1> {
    enum { value = 1 };
};


template<typename T, int N>
struct InverseFactorial {
    static inline T val()
    {
        return T(1) / T(Factorial<N>::value);
    }
};
 

};
#endif // _FACTORIAL_H

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