tnt_math_utils.h

Go to the documentation of this file.

#ifndef MATH_UTILS_H
#define MATH_UTILS_H

/* needed for fabs, sqrt() below */
#include <cmath>



namespace TNT
{
/**
    @returns hypotenuse of real (non-complex) scalars a and b by 
    avoiding underflow/overflow
    using (a * sqrt( 1 + (b/a) * (b/a))), rather than
    sqrt(a*a + b*b).
*/
template <class Real>
Real hypot(const Real &a, const Real &b)
{
    
    if (a== 0)
        return abs(b);
    else
    {
        Real c = b/a;
        return fabs(a) * sqrt(1 + c*c);
    }
}
} /* TNT namespace */



#endif
/* MATH_UTILS_H */