** IMPORTANT: each of these tests requires a different network -- make
   sure that the network is specified correctly in the GNUmakefile

------------------------------------------------------------------------------
spherical test problem from multilevel paper:

  inputs-spherical_heat is the inputs file
 
  This is a test problem for base-state expansion in a full
  white-dwarf environment.  We have a gaussinan bump of heating at the
  center of the star, and a null reaction network.

  ** This needs to be compiled with ignition.net general_null network **
  
  This is a 1D version of spherical_heat.

  Castro output is:

    castro_2sec_den
    castro_2sec_pres
    castro_2sec_temp

  run with the hydrostatic_adjust Castro setup.

  Note that heating_time controls when the heating turns off, which
  will result in w0 going to zero after heating_time seconds of the 
  simulation. 

  Note that total run time is set to a time > heating_time because 
  CASTRO takes additional time to equilibrate after heating is shut off.


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plane-parallel test problem:

  inputs-planar approximates what was done in paper II, but this
  should be revisited.

  The original comparison was done with FLASH


------------------------------------------------------------------------------
analytical CNO cycle test problem:

  make sure to change the nework in GNUmakefile to H_core_null


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planar 1/r**2 gravity nova test problem

   The initial model here was created using initial_models/toy_atm/
   with _params.nova.invsq

   Use the pphotcno network to get the required species

   There is a CASTRO comparison: hydrostatic_adjust_planar_invsq


------------------------------------------------------------------------------
spherical for sub-Chandra

   This is used to test base state expansion for the sub_chandra
   problem.  The model comes from AstroDev/initial_models/sub_chandra.

   This needs to be compiled with one of the triple_alpha networks.

   Castro comparison output is provided: castro_hse_adjust_subchandra.out

  