Key features
============

- Support for other planets

- Radio links

- Zeeman splitting

- Named arguments

- in-ARTS pnd_field calculations from atmospheric fields

- in-ARTS scat_data calculations by Mie or T-matrix


Includes and defaults
=====================

- Default settings have largely been removed from general.arts (1D
scalar clearsky emission is not seen as the default ARTS case anymore)

- "Helper" includes available that set some of the defaults removed from
general.arts (planet*.arts) or that predefine some possible, common
agenda settings (agenda*.arts)

- Standard include file must be prefixed with general/ INCLUDE
"continua.arts" -> INCLUDE "general/continua.arts"


General
=======

- A reference ellipsoid now used

- Sensor position now in altitude

- Appending of y and jacobian variables now possible

- Dispersion can now be handled 

- MC considers now ppath_step_agenda and thus also supports refraction

- possibility for non-scattering particles, i.e. FOS(order=0)
  EXPERIMENTAL!

- Copying of agendas. Used to initialize agendas from defaults, e.g.
Copy(iy_main_agenda, iy_main_agenda__Emission)

- abs_scalar_gas_agenda split into two agendas: abs_xsec_agenda and
propmat_clearsky_agenda

- basics_checkedCalc split into atmfields_checkedCalc, atmgeom_checkedCalc

- New check methods: sensor_checkedCalc,
propmat_clearsky_agenda_checkedCalc, abs_xsec_agenda_checkedCalc

- GriddedFields with atmospheric data must contain correct grid names
attributes: Pressure, Latitude, Longitude etc. (e.g. for AtmRawRead)

- Methods for pressure regridding of atmospheric fields (e.g. AtmFieldsCalc,
GriddedFieldPRegrid, pnd_fieldCalc) allow to fill not explicitly given pressure
levels with zeros (when flag zeropadding set to 1; default remains no
zeropadding)

- Atmospheric dimension must be set explicitly with AtmosphereSet1D or
*2D or *3D

- isotopologue_ratios need to be set explicitly. can be initialized from
isotopologue_ratiosInitFromBuiltin (for Earth) or loaded
from a file (including planet_*.arts loads predefined setups)

- stokes_dim must be explicitly set to 1-4: IndexSet(stokes_dim, 1)

- cloudboxOff and sensorOff must be called explicitly

- DoitInit is required to be called before CloudboxGetIncoming


Naming changes
==============

- InterpSurfaceFieldToRtePos renamed to InterpSurfaceFieldToPosition

- jacobianAddFreqShiftAndStretch split into two separate methods

- SpeciesSet renamed to abs_speciesSet. It also takes more arguments
now. Use new named arguments for easier migration SpeciesSet(
abs_species, ["H2O", "N2-SelfContStandardType", "O3"] ) ->
abs_speciesSet( species=["H2O", "N2-SelfContStandardType", "O3"] )

- y_unit renamed to iy_unit