Functions
void	cart2poslos (double &r, double &lat, double &lon, double &za, double &aa, const double &x, const double &y, const double &z, const double &dx, const double &dy, const double &dz)
	cart2poslos More...

void	cart2sph (double &r, double &lat, double &lon, const double &x, const double &y, const double &z)
	cart2sph More...

Numeric	za_geom2other_point (const Numeric &r1, const Numeric &lat1, const Numeric &r2, const Numeric &lat2)
	za_geom2other_point More...

void	lat_crossing_3d (Numeric &r, Numeric &lon, Numeric &l, const Numeric &lat_hit, const Numeric &lat_start, const Numeric &za_start, const Numeric &x, const Numeric &y, const Numeric &z, const Numeric &dx, const Numeric &dy, const Numeric &dz)
	lat_crossing_3d More...

void	lon_crossing_3d (Numeric &r, Numeric &lat, Numeric &l, const Numeric &lon_hit, const Numeric &lon_start, const Numeric &za_start, const Numeric &aa_start, const Numeric &x, const Numeric &y, const Numeric &z, const Numeric &dx, const Numeric &dy, const Numeric &dz)
	lon_crossing_3d More...

void	plevel_crossing_3d (Numeric &r, Numeric &lat, Numeric &lon, Numeric &l, const Numeric &r_start0, const Numeric &lat_start, const Numeric &lon_start, const Numeric &za_start, const Numeric &aa_start, const Numeric &x, const Numeric &y, const Numeric &z, const Numeric &dx, const Numeric &dy, const Numeric &dz, const Numeric &ppc, const Numeric &lat1, const Numeric &lat3, const Numeric &lon5, const Numeric &lon6, const Numeric &r15, const Numeric &r35, const Numeric &r36, const Numeric &r16, const bool &above)
	plevel_crossing_3d More...

void	do_gridcell_3d (Vector &r_v, Vector &lat_v, Vector &lon_v, Vector &za_v, Vector &aa_v, Numeric &lstep, Index &endface, const Numeric &r_start, const Numeric &lat_start, const Numeric &lon_start, const Numeric &za_start, const Numeric &aa_start, const Numeric &ppc, const Numeric &lmax, const Numeric &lat1, const Numeric &lat3, const Numeric &lon5, const Numeric &lon6, const Numeric &r15a, const Numeric &r35a, const Numeric &r36a, const Numeric &r16a, const Numeric &r15b, const Numeric &r35b, const Numeric &r36b, const Numeric &r16b, const Numeric &rsurface15, const Numeric &rsurface35, const Numeric &rsurface36, const Numeric &rsurface16)
	do_gridcell_3d More...

void	do_gridcell_2d (Vector &r_v, Vector &lat_v, Vector &za_v, Numeric &lstep, Index &endface, const Numeric &r_start, const Numeric &lat_start, const Numeric &za_start, const Numeric &ppc, const Numeric &lmax, const Numeric &lat1, const Numeric &lat3, const Numeric &r1a, const Numeric &r3a, const Numeric &r3b, const Numeric &r1b, const Numeric &rsurface1, const Numeric &rsurface3)
	do_gridcell_2d More...

void	raytrace_1d_linear_basic (Workspace &ws, Array< Numeric > &r_array, Array< Numeric > &lat_array, Array< Numeric > &za_array, Array< Numeric > &l_array, Array< Numeric > &n_array, Array< Numeric > &ng_array, Index &endface, ConstVectorView refellipsoid, ConstVectorView p_grid, ConstVectorView z_field, ConstTensor3View t_field, ConstTensor4View vmr_field, ConstVectorView f_grid, const Numeric &lmax, const Agenda &refr_index_air_agenda, const Numeric &lraytrace, const Numeric &ppc, const Numeric &r_surface, const Numeric &r1, const Numeric &r3, Numeric &r, Numeric &lat, Numeric &za)
	raytrace_1d_linear_basic More...

Function Documentation

◆ cart2poslos()

void cart2poslos	(	double &	r,
		double &	lat,
		double &	lon,
		double &	za,
		double &	aa,
		const double &	x,
		const double &	y,
		const double &	z,
		const double &	dx,
		const double &	dy,
		const double &	dz
	)

cart2poslos

The inverse of poslos2cart.

The azimuth angle is set to:
0 when the zenith angle is 0 or 180. atan2(dy,dx) at the poles (lat = +- 90).

The longitude is set to 0 at the poles (lat = +- 90).

Parameters

r	Out: Radius of observation position.
lat	Out: Latitude of observation position.
lon	Out: Longitude of observation position.
za	Out: LOS zenith angle at observation position.
aa	Out: LOS azimuth angle at observation position.
x	x-coordinate of observation position.
y	y-coordinate of observation position.
z	z-coordinate of observation position.
dx	x-part of LOS unit vector.
dy	y-part of LOS unit vector.
dz	z-part of LOS unit vector.

Author: Patrick Eriksson

Date: 2002-12-30

Definition at line 26 of file ppath_NotUsed.cc.

References abs, ANGTOL, cart2sph(), DEG2RAD, dx, POLELAT, and RAD2DEG.

Referenced by do_gridcell_3d(), and plevel_crossing_3d().

◆ cart2sph()

void cart2sph	(	double &	r,
		double &	lat,
		double &	lon,
		const double &	x,
		const double &	y,
		const double &	z
	)

cart2sph

The inverse of sph2cart.

Parameters

r	Out: Radius of observation position.
lat	Out: Latitude of observation position.
lon	Out: Longitude of observation position.
x	x-coordinate of observation position.
y	y-coordinate of observation position.
z	z-coordinate of observation position.

Author: Patrick Eriksson

Date: 2002-12-30

Definition at line 96 of file ppath_NotUsed.cc.

References RAD2DEG.

Referenced by cart2poslos().

◆ do_gridcell_2d()

void do_gridcell_2d	(	Vector &	r_v,
		Vector &	lat_v,
		Vector &	za_v,
		Numeric &	lstep,
		Index &	endface,
		const Numeric &	r_start,
		const Numeric &	lat_start,
		const Numeric &	za_start,
		const Numeric &	ppc,
		const Numeric &	lmax,
		const Numeric &	lat1,
		const Numeric &	lat3,
		const Numeric &	r1a,
		const Numeric &	r3a,
		const Numeric &	r3b,
		const Numeric &	r1b,
		const Numeric &	rsurface1,
		const Numeric &	rsurface3
	)

do_gridcell_2d

Calculates the geometrical path through a 2D grid cell.

The function determines the geometrical path from the given start point to the boundary of the grid cell. The face where the path exits the grid cell is denoted as the end face. The following number coding is used for the variable endface:
1: The face at the lower latitude point.
2: The face at the lower (geometrically) pressure level.
3: The face at the upper latitude point.
4: The face at the upper (geometrically) pressure level.
7: The end point is an intersection with the surface.

The corner points are names r[lat][a,b]. For example: r3b. The latitudes are numbered to match the end faces. This means that the lower latitude has number 1, and the upper number 3. The pressure levels are named as a and b:
a: Lower pressure level (highest pressure).
b: Upper pressure level (lowest pressure).

Path points are included if lmax>0 and the distance to the end point is > than lmax.

The return vectors (r_v etc.) can have any length when handed to the function.

Parameters

r_v	Out: Vector with radius of found path points.
lat_v	Out: Vector with latitude of found path points.
za_v	Out: Vector with LOS zenith angle at found path points.
lstep	Out: Vector with length along the path between points.
endface	Out: Number coding for exit face. See above.
r_start0	Radius of start point.
lat_start	Latitude of start point.
za_start	LOS zenith angle at start point.
ppc	Propagation path constant.
lmax	Maximum allowed length along the path. -1 = no limit.
lat1	Latitude of left end face (face 1) of the grid cell.
lat3	Latitude of right end face (face 3) of the grid cell.
r1a	Radius of lower-left corner of the grid cell.
r3a	Radius of lower-right corner of the grid cell.
r3b	Radius of upper-right corner of the grid cell (r3b>r3a)
r1b	Radius of upper-left corner of the grid cell (r1b>r1a).
rsurface1	Radius for the surface at lat1.
rsurface3	Radius for the surface at lat3.

Author: Patrick Eriksson

Date: 2002-11-28

Definition at line 842 of file ppath_NotUsed.cc.

References abs, geompath_from_r1_to_r2(), geompath_r_at_lat(), L_NOT_FOUND, ConstVectorView::nelem(), and plevel_crossing_2d().

◆ do_gridcell_3d()

void do_gridcell_3d	(	Vector &	r_v,
		Vector &	lat_v,
		Vector &	lon_v,
		Vector &	za_v,
		Vector &	aa_v,
		Numeric &	lstep,
		Index &	endface,
		const Numeric &	r_start,
		const Numeric &	lat_start,
		const Numeric &	lon_start,
		const Numeric &	za_start,
		const Numeric &	aa_start,
		const Numeric &	ppc,
		const Numeric &	lmax,
		const Numeric &	lat1,
		const Numeric &	lat3,
		const Numeric &	lon5,
		const Numeric &	lon6,
		const Numeric &	r15a,
		const Numeric &	r35a,
		const Numeric &	r36a,
		const Numeric &	r16a,
		const Numeric &	r15b,
		const Numeric &	r35b,
		const Numeric &	r36b,
		const Numeric &	r16b,
		const Numeric &	rsurface15,
		const Numeric &	rsurface35,
		const Numeric &	rsurface36,
		const Numeric &	rsurface16
	)

do_gridcell_3d

Calculates the geometrical path through a 3D grid cell.

The function determines the geometrical path from the given start point to the boundary of the grid cell. The face where the path exits the grid cell is denoted as the end face. The same number coding as in do_gridcell_2d is used, where the additional longitude end faces are numbered as:
5: The face at the lower longitude point.
6: The face at the upper longitude point.

The corner points are numbered as do_gridcell_2d, but 5 or 6 is added after the latitude number to indicate the longitude. This means that r16a, is the corner at lat1, lon6 and pressure level a.

See further do_gridcell_2d.

Parameters

r_v	Out: Vector with radius of found path points.
lat_v	Out: Vector with latitude of found path points.
lon_v	Out: Vector with longitude of found path points.
za_v	Out: Vector with LOS zenith angle at found path points.
aa_v	Out: Vector with LOS azimuth angle at found path points.
lstep	Out: Vector with length along the path between points.
endface	Out: Number coding for exit face. See above.
r_start0	Radius of start point.
lat_start0	Latitude of start point.
lon_start0	Longitude of start point.
za_start	LOS zenith angle at start point.
aa_start	LOS azimuth angle at start point.
ppc	Propagation path constant.
lmax	Maximum allowed length along the path. -1 = no limit.
lat1	Latitude of left end face (face 1) of the grid cell.
lat3	Latitude of right end face (face 3) of the grid cell.
lon5	Lower longitude limit of the grid cell.
lon6	Upper longitude limit of the grid cell.
r15a	Radius of corner: lower p-level,lat1 and lon5.
r35a	Radius of corner: lower p-level,lat3 and lon5.
r36a	Radius of corner: lower p-level,lat3 and lon6.
r16a	Radius of corner: lower p-level,lat1 and lon6.
r15b	Radius of corner: upper p-level,lat1 and lon5.
r35b	Radius of corner: upper p-level,lat3 and lon5.
r36b	Radius of corner: upper p-level,lat3 and lon6.
r16b	Radius of corner: upper p-level,lat1 and lon6.
rsurface15	Radius for the surface at lat1 and lon5.
rsurface35	Radius for the surface at lat3 and lon5.
rsurface36	Radius for the surface at lat3 and lon6.
rsurface16	Radius for the surface at lat1 and lon6.

Author: Patrick Eriksson

Date: 2002-11-28

Definition at line 613 of file ppath_NotUsed.cc.

References abs, cart2poslos(), dx, geompath_l_at_r(), geompath_tanpos_3d(), geompath_za_at_r(), L_NOT_FOUND, LACC, lat_crossing_3d(), lon_crossing_3d(), plevel_crossing_3d(), poslos2cart(), Vector::resize(), and resolve_lon().

◆ lat_crossing_3d()

void lat_crossing_3d	(	Numeric &	r,
		Numeric &	lon,
		Numeric &	l,
		const Numeric &	lat_hit,
		const Numeric &	lat_start,
		const Numeric &	za_start,
		const Numeric &	x,
		const Numeric &	y,
		const Numeric &	z,
		const Numeric &	dx,
		const Numeric &	dy,
		const Numeric &	dz
	)

lat_crossing_3d

Calculates where a 3D LOS crosses the specified latitude

The solution algorithm is described in ATD. See the chapter on propagation paths.

The function only looks for crossings in the forward direction of the given zenith angle (neglecting all solutions giving l <= 0). Note that the tangent point can be passed.

R_NOT_FOUND, LON_NOT_FOUND and L_NOT_FOUND are returned if no solution is found.

Parameters

r	Out: Radius of found crossing.
lon	Out: Longitude of found crossing.
l	Out: Length along the path to the crossing.
lat_hit	Target latitude.
lat_start	Latitude of start point.
aa_start	Azimuth angle at start point.
x	x-coordinate of start position.
y	y-coordinate of start position.
z	z-coordinate of start position.
dx	x-part of LOS unit vector.
dy	y-part of LOS unit vector.
dz	z-part of LOS unit vector.

Author: Patrick Eriksson

Date: 2012-02-29

Definition at line 190 of file ppath_NotUsed.cc.

References abs, DEG2RAD, dx, L_NOT_FOUND, LON_NOT_FOUND, max, min, R_NOT_FOUND, RAD2DEG, and sign().

Referenced by do_gridcell_3d().

◆ lon_crossing_3d()

void lon_crossing_3d	(	Numeric &	r,
		Numeric &	lat,
		Numeric &	l,
		const Numeric &	lon_hit,
		const Numeric &	lon_start,
		const Numeric &	za_start,
		const Numeric &	aa_start,
		const Numeric &	x,
		const Numeric &	y,
		const Numeric &	z,
		const Numeric &	dx,
		const Numeric &	dy,
		const Numeric &	dz
	)

lon_crossing_3d

Calculates where a 3D LOS crosses the specified longitude.

The solution algorithm is described in ATD. See the chapter on propagation paths.

The function only looks for crossings in the forward direction of the given zenith angle (neglecting all solutions giving l <= 0). Note that the tangent point can be passed.

R_NOT_FOUND, LAT_NOT_FOUND and L_NOT_FOUND are returned if no solution is found.

Parameters

r	Out: Radius of found crossing.
lat	Out: Latitude of found crossing.
l	Out: Length along the path to the crossing.
lon_hit	Target longitude.
lon_start	Longitude of start position.
za_start	Zenith angle at start position.
aa_start	Azimuth angle at start position.
x	x-coordinate of start position.
y	y-coordinate of start position.
z	z-coordinate of start position.
dx	x-part of LOS unit vector.
dy	y-part of LOS unit vector.
dz	z-part of LOS unit vector.

Author: Patrick Eriksson

Date: 2012-02-29

Definition at line 311 of file ppath_NotUsed.cc.

References abs, DEG2RAD, dx, L_NOT_FOUND, LAT_NOT_FOUND, R_NOT_FOUND, and RAD2DEG.

Referenced by do_gridcell_3d().

◆ plevel_crossing_3d()

void plevel_crossing_3d	(	Numeric &	r,
		Numeric &	lat,
		Numeric &	lon,
		Numeric &	l,
		const Numeric &	r_start0,
		const Numeric &	lat_start,
		const Numeric &	lon_start,
		const Numeric &	za_start,
		const Numeric &	aa_start,
		const Numeric &	x,
		const Numeric &	y,
		const Numeric &	z,
		const Numeric &	dx,
		const Numeric &	dy,
		const Numeric &	dz,
		const Numeric &	ppc,
		const Numeric &	lat1,
		const Numeric &	lat3,
		const Numeric &	lon5,
		const Numeric &	lon6,
		const Numeric &	r15,
		const Numeric &	r35,
		const Numeric &	r36,
		const Numeric &	r16,
		const bool &	above
	)

plevel_crossing_3d

As plevel_crossing_2d but for 3D

Parameters

r	Out: Radius at crossing.
lat	Out: Latitude at crossing.
lon	Out: Longitude at crossing.
l	Out: Distance between start and crossing points.
r_start0	In: Radius of start point.
lat_start	In: Latitude of start point.
lon_start	In: Longitude of start point.
za_start	In: LOS zenith angle at start point.
aa_start	In: LOS azimuth angle at start point.
ppc	In: Propagation path constant.
lat1	In: Latitude of lower end.
lat3	In: Latitude of upper end.
lon5	In: Longitude of lower end.
lon6	In: Longitude of upper end.
r15	In: Radius at lat1/lon5.
r35	In: Radius at lat3/lon5.
r36	In: Radius at lat3/lon6.
r16	In: Radius at lat1/lon6.
x	In: x-coordinate of start position.
y	In: y-coordinate of start position.
z	In: z-coordinate of start position.
dx	In: x-part of LOS unit vector.
dy	In: y-part of LOS unit vector.
dz	In: z-part of LOS unit vector.
above	In: True if ppath start point is above level. In: Otherwise false.

Author: Patrick Eriksson

Date: 2012-02-19

Definition at line 384 of file ppath_NotUsed.cc.

References abs, ANGTOL, cart2poslos(), distance3D(), dx, L_NOT_FOUND, LAT_NOT_FOUND, latlon_at_aa(), LON_NOT_FOUND, max, min, plevel_slope_3d(), r_crossing_3d(), R_NOT_FOUND, resolve_lon(), rslope_crossing3d(), rsurf_at_latlon(), and RTOL.

Referenced by do_gridcell_3d().

◆ raytrace_1d_linear_basic()

void raytrace_1d_linear_basic	(	Workspace &	ws,
		Array< Numeric > &	r_array,
		Array< Numeric > &	lat_array,
		Array< Numeric > &	za_array,
		Array< Numeric > &	l_array,
		Array< Numeric > &	n_array,
		Array< Numeric > &	ng_array,
		Index &	endface,
		ConstVectorView	refellipsoid,
		ConstVectorView	p_grid,
		ConstVectorView	z_field,
		ConstTensor3View	t_field,
		ConstTensor4View	vmr_field,
		ConstVectorView	f_grid,
		const Numeric &	lmax,
		const Agenda &	refr_index_air_agenda,
		const Numeric &	lraytrace,
		const Numeric &	ppc,
		const Numeric &	r_surface,
		const Numeric &	r1,
		const Numeric &	r3,
		Numeric &	r,
		Numeric &	lat,
		Numeric &	za
	)

raytrace_1d_linear_basic

Performs ray tracing for 1D with linear steps.

A geometrical step with length of lraytrace is taken from each point. The zenith angle for the end point of that step is calculated exactly by the expression c = r*n*sin(theta), and a new step is taken. The length of the last ray tracing step to reach the end radius is adopted to the distance to the end radius.

The refractive index is assumed to vary linearly between the pressure levels.

As the ray tracing is performed from the last end point, the found path will not be symmetric around the tangent point.

For more information read the chapter on propagation paths in AUG. The algorithm used is described in that part of ATD.

Parameters

ws	Current Workspace
r_array	Out: Radius of ray tracing points.
lat_array	Out: Latitude of ray tracing points.
za_array	Out: LOS zenith angle at ray tracing points.
l_array	Out: Distance along the path between ray tracing points.
n_array	Out: Refractive index at ray tracing points.
ng_array	Out: Group refractive index at ray tracing points.
endface	See do_gridrange_1d.
refellipsoid	As the WSV with the same name.
p_grid	Pressure grid.
z_field	Geometrical altitudes (1D).
t_field	As the WSV with the same name.
vmr_field	As the WSV with the same name.
f_grid	As the WSV with the same name.
lmax	As the WSV ppath_lmax
refr_index_air_agenda	As the WSV with the same name.
lraytrace	Maximum allowed length for ray tracing steps.
ppc	Propagation path constant.
r_surface	Radius of the surface.
r1	Radius of lower pressure level.
r3	Radius of upper pressure level (r3 > r1).
r	Start radius for ray tracing.
lat	Start latitude for ray tracing.
za	Start zenith angle for ray tracing.

Author: Patrick Eriksson

Date: 2002-12-02

Definition at line 971 of file ppath_NotUsed.cc.

References abs, DEG2RAD, do_gridrange_1d(), geometrical_ppc(), geompath_l_at_r(), geompath_lat_at_za(), geompath_r_at_l(), geompath_za_at_r(), get_refr_index_1d(), ConstVectorView::nelem(), and RTOL.

◆ za_geom2other_point()

Numeric za_geom2other_point	(	const Numeric &	r1,
		const Numeric &	lat1,
		const Numeric &	r2,
		const Numeric &	lat2
	)

za_geom2other_point

Calculates the zenith angle for the geometrical propagation path between two specified points.

The returned zenith angle is valid for point 1. That is, the propagation path goes from point 1 to point 2.

Returns: Zenith angle.

Parameters

r1	Radius for point 1.
lat1	Latiytude for point 1.
r2	Radius for point 2.
lat2	Latitude for point 2.

Author: Patrick Eriksson

Date: 2002-07-03

Definition at line 128 of file ppath_NotUsed.cc.

References abs, DEG2RAD, and RAD2DEG.

Functions

Function Documentation

◆ cart2poslos()

◆ cart2sph()

◆ do_gridcell_2d()

◆ do_gridcell_3d()

◆ lat_crossing_3d()

◆ lon_crossing_3d()

◆ plevel_crossing_3d()

◆ raytrace_1d_linear_basic()

◆ za_geom2other_point()