Function sqrtf

include/std/math.h:16–41

#if __MWERKS__ > 0x2301
extern inline float sqrtf(float x)
{
    static const double _half = .5f;
    static const double _three = 3.0f;
    if (x > 0.0f)
    {
        double xd = (double)x;
        double guess = __frsqrte(xd);                          // returns an approximation to
        guess = _half * guess * (_three - guess * guess * xd); // now have 12 sig bits
        guess = _half * guess * (_three - guess * guess * xd); // now have 24 sig bits
        guess = _half * guess * (_three - guess * guess * xd); // now have 32 sig bits
        return (float)(xd * guess);
    }
    else if (x < 0.0)
    {
        return NAN;
    }
    else if (isnan(x))
    {
        return NAN;
    }
    else
    {
        return x;
    }
}
#else
extern inline float sqrtf(float x)
{