Changed the naming of the single S-parameter graphs from S<n><n> to S<n>_<n> in order to correctly deal with the case where there are more than nine ports.
Changed the naming of the single S-parameter graphs from S<n><n> to S<n>_<n> in order to correctly deal with the case where there are more than nine ports.

alunmorgan/GdfidL-framework,alunmorgan/GdfidL-framework,alunmorgan/EM-modellling-framework