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Workspace Method MCGeneral


A generalised 3D reversed Monte Carlo radiative algorithm, that
allows for 2D antenna patterns, surface reflection and arbitrary
sensor positions.

The main output variables y and mc_error represent the
Stokes vector integrated over the antenna function, and the
estimated error in this vector, respectively.

The WSV mc_max_iter describes the maximum number of `photons'
used in the simulation (more photons means smaller mc_error).
mc_std_err is the desired value of mc_error. mc_max_time is
the maximum allowed number of seconds for MCGeneral. The method
will terminate once any of the max_iter, std_err, max_time
criteria are met. If negative values are given for these
parameters then it is ignored.

The WSV mc_min_iter sets the minimum number of photons to apply
before the condition set by mc_std_err is considered. Values
of mc_min_iter below 100 are not accepted.

Only "1" and "RJBT" are allowed for iy_unit. The value of
mc_error follows the selection for iy_unit (both for in- and

Authors: Cory Davis


MCGeneral( y, mc_iteration_count, mc_error, mc_points, mc_source_domain, mc_scat_order, mc_antenna, f_grid, f_index, sensor_pos, sensor_los, stokes_dim, atmosphere_dim, ppath_step_agenda, ppath_lmax, ppath_lraytrace, iy_space_agenda, surface_rtprop_agenda, propmat_clearsky_agenda, p_grid, lat_grid, lon_grid, z_field, refellipsoid, z_surface, t_field, vmr_field, cloudbox_on, cloudbox_limits, pnd_field, scat_data, atmfields_checked, atmgeom_checked, scat_data_checked, cloudbox_checked, iy_unit, mc_seed, mc_std_err, mc_max_time, mc_max_iter, mc_min_iter, mc_taustep_limit, l_mc_scat_order, t_interp_order )


OUTy(Vector)The measurement vector.
OUTmc_iteration_count(Index)Counts the number of iterations (or photons) used in the MC scattering algorithm.
OUTmc_error(Vector)Error in simulated y when using a Monte Carlo approach.
OUTmc_points(Tensor3)Source to emission, position.
OUTmc_source_domain(ArrayOfIndex)Rough classification of source to emission.
OUTmc_scat_order(ArrayOfIndex)Number of atmospheric scattering events between emission point and sensor.
INmc_antenna(MCAntenna)Antenna pattern description for dedicated MC calculaions.
INf_grid(Vector)The frequency grid for monochromatic pencil beam calculations.
INf_index(Index)Frequency index.
INsensor_pos(Matrix)The sensor position for each measurement block.
INsensor_los(Matrix)The sensor line-of-sight (LOS) for each measurement block.
INstokes_dim(Index)The dimensionality of the Stokes vector (1-4).
INatmosphere_dim(Index)The atmospheric dimensionality (1-3).
INppath_step_agenda(Agenda)Agenda calculating a propagation path step.
INppath_lmax(Numeric)Maximum length between points describing propagation paths.
INppath_lraytrace(Numeric)Maximum length of ray tracing steps when determining propagation paths.
INiy_space_agenda(Agenda)Agenda providing the downwelling radiation at the top of the atmosphere.
INsurface_rtprop_agenda(Agenda)Agenda providing radiative properties of the surface.
INpropmat_clearsky_agenda(Agenda)Agenda calculating the absorption coefficient matrices.
INp_grid(Vector)The pressure grid.
INlat_grid(Vector)The latitude grid.
INlon_grid(Vector)The longitude grid.
INz_field(Tensor3)The field of geometrical altitudes.
INrefellipsoid(Vector)Reference ellipsoid.
INz_surface(Matrix)The surface altitude.
INt_field(Tensor3)The field of atmospheric temperatures.
INvmr_field(Tensor4)VMR field.
INcloudbox_on(Index)Flag to activate the cloud box.
INcloudbox_limits(ArrayOfIndex)The limits of the cloud box.
INpnd_field(Tensor4)Particle number density field.
INscat_data(ArrayOfArrayOfSingleScatteringData)Array of single scattering data.
INatmfields_checked(Index)OK-flag for atmospheric grids and (physical) fields.
INatmgeom_checked(Index)OK-flag for the geometry of the model atmosphere.
INscat_data_checked(Index)OK-flag for scat_data.
INcloudbox_checked(Index)OK-flag for variables associated with the cloudbox.
INiy_unit(String)Selection of output unit for radiative transfer methods.
INmc_seed(Index)The integer seed for the random number generator used by Monte Carlo methods.
INmc_std_err(Numeric)Target precision (1 std.
INmc_max_time(Index)The maximum time allowed for Monte Carlo calculations.
INmc_max_iter(Index)The maximum number of iterations allowed for Monte Carlo calculations.
INmc_min_iter(Index)The minimum number of iterations allowed for Monte Carlo calculations.
INmc_taustep_limit(Numeric)Defines an upper step length in terms of optical thickness for Monte Carlo calculations.
GINl_mc_scat_order(Index, Default: 11)The length to be given to mc_scat_order. Note that scattering orders equal and above this value will not be counted.
GINt_interp_order(Index, Default: 1)Interpolation order of temperature for scattering data (so far only applied in phase matrix, not in extinction and absorption.