I am about to make a commit with some major changes. Richard, Jana and I
have since the ARTS workshop worked on streamlining the radiative
transfer methods, with the aim of having a coherent internal system
covering both non-LTE and scattering, as well as simplifying and
extending the calculation of analytical Jacobians. On the same time,
some changes around ppath and auxiliary data have been introduced.
The methods iyEmissionStandard, iyTransmissionStandard and
iyActiveSingleScat are largely rewritten. Most of the changes are just
seen on the inside. There could be some small impact on the main
outputs, iy and the resulting Jacobian. This due to slightly changed
approach on how variables are averaged over a ppath step. But the
differences we have seen so far all have been negligible.
On the other hand, a main change is that ppath is now calculated outside
of the iy-methods. This for increased flexibility, and make it possible
to avoid recalculating the ppath for e.g. iterative OEM inversions. This
means that you need to call ppathCalc inside or outside of
iy_main_agenda (if outside, you need Touch(ppath) inside the agenda).
Note that the definitions in agendas.arts are updated and likely you
don't need to care about this.
The treatment of "aux-variables" has also changed. Various atmospheric
and radiative properties along the ppath, are now exported as
pre-defined WSVs. These variables are denoted as ppvar_something (ppvar
= propagation path variable). One example is ppvar_t, that gives you the
temperature at each point of the ppath.
iy_aux_vars is now reduced to only treat variables that can be expressed
as a matrix, as iy itself, such as (total) optical depth. As a
consequence, iy_aux is now an ArrayOfMatrix. And all iy_ayx_vars can now
be passed on to y_aux. However, I have not got time to resurrect all
iy_aux_vars (such as Faraday rotation), and little testing done. So
don't expect to much of this part yet.
Some documentation updated, but a lot to on that side ...
We think these changes will make it easier to use and develop ARTS in
the long run, but could cause some problems now. Tell us if you obtain
any suspicious results, or if any feature you use has disappeared.
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