[Binning]

This section deals with the resampling of the forward model.

Binning allows you to change how the forward is sampled. When only running in forward model mode, it affects the final binned spectrum stored in the output and the plotting. It has no effect on retrievals.

The type of binning defined is given by the bin_type variable:

The available bin_type are:

• native

  • Spectra is not resampled

  • Default when no [Observation] is given

• observed

  • Resample to observation grid

  • Default when [Observation] is given

• manual

  • Manually defined resample grid

Manual binning

bin_type = manual

When set to manual, you can then define the start, end and number of points of the grid using one of these keywords:

Variable	Description
wavelength_grid	Equally spaced grid in wavelength (um)
wavenumber_grid	Equally spaced grid in wavenumber (cm-1)
log_wavelength_grid	Equally log-spaced grid in wavelength (um)
log_wavenumber_grid	Equally log-spaced grid in wavenumber (cm-1)

An example, to define an equally spaced wavelength grid at 0.3-5 um:

[Binning]
bin_type = manual
wavelength_grid = 0.3, 5, 300

Or define an equally log spaced wavenumber grid between 400-5000 cm-1:

[Binning]
bin_type = manual
log_wavenumber_grid = 400, 5000, 300

Alternativly you can instead define it based on the resolution with the format as start, end, resolution

Variable	Description
wavelength_res	Wavelength grid at resolution (um)

We can define a grid with 1.1-1.7 um at R=50 resolution:

[Binning]
bin_type = manual
wavelength_res = 1.1, 1.7, 50

Finally there is an optional parameter accurate. When False, a simpler histogramming method is used to perform the resampling. When set to True a more accurate method is used that takes into account the occupancy of each native sample on the sampling grid.