Operators.tpp

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// Operator "sign" ------------------------------------------------------------------- //
template <class T>
T sign(
        const  T                & val
      ){
    return (T(0) < val) - (val < T(0)) ;
};

template <class T>
T uipow(const T & base, unsigned int exponent)
{
    switch (exponent) {
 
    case 0:
    {
        return 1;
    }
 
    case 1:
    {
        return base;
    }
 
    case 2:
    {
        return base * base;
    }
 
    case 3:
    {
        return base * base * base;
    }
 
    default:
    {
        // The integer power is evluated using the exponentiating by squaring
        // algorithm. For an explanation of the algorith see the following
        // link:
        //
        //    https://en.wikipedia.org/wiki/Exponentiation_by_squaring
        T result = static_cast<T>(1);
        T base_work = base;
        while (exponent) {
            if (exponent % 2) {
                result *= base_work;
            }
 
            exponent /= 2;
            base_work *= base_work;
        }
 
        return result;
    }
 
    }
}