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Workspace Method jacobianAddFreqStretch

Description

Includes a frequency for of stretch type in the Jacobian.

Retrieval of deviations between nominal and actual backend
frequencies can be included by this method. The assumption here is
that the deviation varies linearly over the frequency range
(following ARTS basis function for polynomial order 1).

The frequency shift can be modelled to be time varying. The time
variation is then described by a polynomial (with standard base
functions). For example, a polynomial order of 0 means that the
shift is constant in time. If the shift is totally uncorrelated
between the spectra, set the order to -1.

Authors: Patrick Eriksson

Synopsis

jacobianAddFreqStretch(

jacobian_quantities, jacobian_agenda, f_grid, sensor_pos, sensor_time, poly_order, df )

Variables

OUT+IN	jacobian_quantities	(ArrayOfRetrievalQuantity)	The retrieval quantities in the Jacobian matrix.
OUT+IN	jacobian_agenda	(Agenda)	See agendas.cc.
IN	f_grid	(Vector)	The frequency grid for monochromatic pencil beam calculations.
IN	sensor_pos	(Matrix)	The sensor position for each measurement block.
IN	sensor_time	(Vector)	The time for each measurement block.
GIN	poly_order	(Index, Default: 0)	Order of polynomial to describe the time variation of frequency stretch.
GIN	df	(Numeric, Default: 100e3)	Size of perturbation to apply.