Validation of DSST C/C++ against original Fortran version: integration test

The migration of the Fortran-77 DSST Standalone implementation of the Semi-analytical Method of Orbit Computation (SMC) code to the C/C++ platform is described. The aim is to port the F77 DSST logical structure from the original F77 version to form a C version that is faithful to the original design. An important consequence of this approach is the retention of tried and tested numerical algorithms without drastic degradation of the run-time performance of the DSST. To this end, an incremental re-engineering strategy was adopted for the implementation of this project. The first stage of this project is described in this paper, with results from the current validation and verification process of the DSST C/C++ version against the original F77 DSST.