simple.hpp

Go to the documentation of this file.

 
/*****************************************************************************
** Ifdefs
*****************************************************************************/
 
#ifndef ECL_CORE_MATH_SIMPLE_HPP_
#define ECL_CORE_MATH_SIMPLE_HPP_
 
/*****************************************************************************
** Includes
*****************************************************************************/
 
#include <cmath>
 
/*****************************************************************************
** Namespaces
*****************************************************************************/
 
namespace ecl {
 
/*****************************************************************************
** Functions
*****************************************************************************/
template <typename Scalar>
inline int sign(const Scalar &x) {
        // ToDo: should probably check some numeric traits here
        // Is this faster? (v > 0) - (v < 0);
        // http://stackoverflow.com/questions/1903954/is-there-a-standard-sign-function-signum-sgn-in-c-c
        if ( x > 0 ) {
                return 1;
        } else if ( x < 0 ) {
                return -1;
        } else {
                return 0;
        }
}
 
template <typename Scalar>
inline int psign(const Scalar &x) {
        // ToDo: should probably check some numeric traits here
        if ( x >= 0 ) {
                return 1;
        } else {
                return -1;
        }
}
 
template <typename Scalar>
inline int nsign(const Scalar &x) {
        // ToDo: should probably check some numeric traits here
        if ( x > 0 ) {
                return 1;
        } else {
                return -1;
        }
}
 
template <typename Scalar>
inline Scalar cube_root(const Scalar &x) {
        // ToDo: should probably check some numeric traits here
        return psign(x)*pow(fabs(x),1.0/3.0);
}
 
 
} // namespace ecl
 
#endif /* ECL_CORE_MATH_SIMPLE_HPP_ */