The primary entry point to the eos module is through the routine eosDT_get. Broadly, one provides the density, temperature and full composition information. Then the EOS returns its main set of results, their temperature and density derivatives, and the composition derivatives of a small subset of the results.
.. literalinclude:: ../../../eos/public/eos_lib.f90 :language: fortran :start-at: subroutine eosDT_get :end-at: end subroutine eosDT_get :linenos:
The underlying EOS is in a density-temperature basis, but if one has only density or temperature, there are search interfaces (eosDT_get_Rho and eosDT_get_T) for searching for the other, given some another known EOS quantity (e.g., lnE).
.. literalinclude:: ../../../eos/public/eos_lib.f90 :language: fortran :start-at: subroutine eosDT_get_T :end-at: end subroutine eosDT_get_T :linenos:
For legacy reasons, there is also an eosPT_get entry point. (The same result could ultimately be achieved via eosDT_get_Rho.) Internally, this is also implemented as a root-find using the standard density-temperature EOS.
.. literalinclude:: ../../../eos/public/eos_lib.f90 :language: fortran :start-at: subroutine eosPT_get :end-at: end subroutine eosPT_get :linenos: