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Workspace Method jacobianAddFreqShiftAndStretch

Description

Includes a frequency fit in the Jacobian.

Retrieval of deviations between nominal and actual backend
frequencies can be included by this method. The calculations can be
performed in the following ways:
   calcmode = "interp": Interpolation of monochromatic spectra,
      shifted with *df* from nominal values.

The frequencies can be fitted with 1 or 2 variables. The first one
is a "shift". That is, an off-set common for all backend channels.
The second variable is "stretch", that is included only if
*do_stretch* is set to 1. The stretch is a frequency shift that goes
from -x at the first channel and increases linearly to reach x at
the last channel, where x is the retrieved value.

Authors: Patrick Eriksson

Synopsis

jacobianAddFreqShiftAndStretch(

jacobian_quantities, jacobian_agenda, f_grid, calcmode, df, do_stretch )

Variables

OUT	jacobian_quantities	(ArrayOfRetrievalQuantity)	The retrieval quantities in the Jacobian matrix.
OUT	jacobian_agenda	(Agenda)	See agendas.cc.
IN	jacobian_quantities	(ArrayOfRetrievalQuantity)	The retrieval quantities in the Jacobian matrix.
IN	jacobian_agenda	(Agenda)	See agendas.cc.
IN	f_grid	(Vector)	The frequency grid for monochromatic pencil beam calculations.
GIN	calcmode	(String, Default: "interp")	Calculation method. See above
GIN	df	(Numeric, Default: 100e3)	Size of perturbation to apply.
GIN	do_stretch	(Index, Default: 0)	Flag to also include frequency stretch.