The astrodynamics calculations are all implemented as static functions in the SGP4 class/module. The ElsetRec datastructure is used to maintain initialization state across those methods. For convenience, I have implemented the TLE class. The constructor accepts the two lines of the the two-line element set as arguments. To then propagate (simulate) the orbit, I have implemented a few getRV methods in each language. One will accept the number of minutes since the epoch as an argument. In most languages, I've also implemented a version of getRV that accepts a Date or DateTime object to simulate the orbit at a specific point in time. Sometimes, if I didn't find a helper class in the target language that I liked, I simply used the number of milliseconds since January 1, 1970 as the argument.

*[C](#c)

*[C++](#c-1)

*[C#](#c-2)

*[FORTRAN 90](#fortran-90)

*[Java](#java)

*[JavaScript](#javascript)

*[LibreOffice Basic](#libreoffice-basic)

*[Matlab/Octave](#matlaboctave)

*[Python 2/3](#python)

*[R](#r)

*[Ruby](#ruby)

gcc -o testsgp4 SGP4.c TLE.c TestSGP4.c -lm

The SGP4 and TLE code works in both Python 2 and Python 3. The TestSGP4 code should also work in both versions and has a dependency on the standard json package. Simply execute your preferred version of python from the python src directory.

python2 TestSGP4.py

Typical Errors

0.00651341005177

mm

0.000481251231334

mm/s

python3 TestSGP4.py

Typical Errors

0.006513410051766991