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Workspace Method jacobianAddPolyfit
Includes polynomial baseline fit in the Jacobian.
This method deals with retrieval of disturbances of the spectra
that can be described by an additive term, a baseline off-set.
The baseline off-set is here modelled as a polynomial. The
polynomial spans the complete frequency range spanned by
sensor_response_f_grid and the method should only of interest for
cases with no frequency gap in the spectra. The default assumption
is that the off-set differs between all spectra, but it can also be
assumed that the off-set is common for all e.g. line-of-sights.
If the simulation/retrieval deals with a single spectrum, the number
of elements added to the state vector (x) is poly_order+1. The
coefficient for polynomial order 0 comes first etc. The same is true
if *no_pol_variation*, *no_los_variation* and *no_mblock_variation*
all are set to 1, even if several spectra are involved. Otherwise thenumber of elements added to x depends on the number of spectra and
the settings of *no_pol_variation*, *no_los_variation* and
*no_mblock_variation*. The coefficients of the different polynomial
orders are treated as separate retrieval quantities. That is, the
the elements associated with polynomial order 0 are grouped and form
together a retrieval quantity. The coefficients for higher polynomial
orders are treated in the same way.
Authors: Patrick Eriksson