scalarI.H

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#include "scalar.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
inline Foam::scalar Foam::integerPow(const scalar x, const label e)
{
    if (e == 0)
    {
        return 1;
    }
 
    scalar xx = e > 0 ? x : 1/x;
 
    scalar y = 1;
 
    for (label i = e; i != 0; i /= 2)
    {
        if (i % 2)
        {
            y *= xx;
        }
 
        xx *= xx;
    }
 
    return y;
}
 
 
inline Foam::scalar Foam::integerRoot(const scalar x, const label e)
{
    switch (e)
    {
        case -4: return 1/pow025(x);
        case -3: return 1/cbrt(x);
        case -2: return 1/sqrt(x);
        case -1: return 1/x;
        case 0: return NaN;
        case 1: return x;
        case 2: return sqrt(x);
        case 3: return cbrt(x);
        case 4: return pow025(x);
    }
 
    return pow(x, scalar(1)/e);
}
 
 
// ************************************************************************* //