#ifndef _sgp4ext_
#define _sgp4ext_
/*     ----------------------------------------------------------------
*
*                                 sgp4ext.h
*
*    this file contains extra routines needed for the main test program for sgp4.
*    these routines are derived from the astro libraries.
*
*                            companion code for
*               fundamentals of astrodynamics and applications
*                                    2007
*                              by david vallado
*
*       (w) 719-573-2600, email dvallado@agi.com
*
*    current :
*              20 apr 07  david vallado
*                           misc documentation updates
*    changes :
*              14 aug 06  david vallado
*                           original baseline
*       ----------------------------------------------------------------      */

#include <string.h>
#include <math.h>

// ------------------------- function declarations -------------------------

double  sgn
        (
          double
        );

double  mag
        (
          double[]
        );

void    cross
        (
          double[], double[], double[]
        );

double  dot
        (
          double[] , double[]
        );

double  angle
        (
          double[],
          double[]
        );

void    newtonnu
        (
          double ecc, double nu,
          double& e0, double& m
        );

void    rv2coe
        (
          double[], double[], double,
          double&, double&, double&, double&, double&, double&,
          double&, double&, double&, double&, double&
        );

void    jday
        (
          int, int, int, int, int, double, double&
        );

void    days2mdhms
        (
          int, double, int&, int&, int&, int&, double&
        );

void    invjday
        (
          double, int&, int&, int&, int&, int&, double&
        );

#endif