void sphlat_c ( SpiceDouble r,
SpiceDouble colat,
SpiceDouble lons,
SpiceDouble * radius,
SpiceDouble * lon,
SpiceDouble * lat )
Convert from spherical coordinates to latitudinal coordinates.
None.
CONVERSION, COORDINATES
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
r I Distance of the point from the origin.
colat I Angle of the point from positive z axis (radians).
lons I Angle of the point from the XZ plane (radians).
radius O Distance of a point from the origin
lon O Angle of the point from the XZ plane in radians
lat O Angle of the point from the XY plane in radians
r Distance of the point from the origin.
colat Angle between the vector from the origin to the point
and the positive z axis in radians.
lons Angle of the point from the XZ plane (radians).
radius Distance of a point from the origin
lon Angle of the point from the XZ plane in radians. `lon'
is set equal to `lons'.
lat Angle of the point from the XY plane in radians. `lat'
is computed as pi/2 - `colat'.
None.
Error free.
None.
This routine returns the latitudinal coordinates of a point
whose position is input in spherical coordinates.
Latitudinal coordinates are defined by a distance from a central
reference point, an angle from a reference meridian, and an angle
above the equator of a sphere centered at the central reference
point.
Spherical coordinates are defined by a distance from a central
reference point, an angle from a reference meridian, and an angle
from the z-axis.
Latitude is obtained by subtracting co-latitude from HALFPI()
Radius and longitude mean the same thing in both latitudinal
and spherical coordinates. The table below lists lat and
corresponding colat in terms of degrees.
lat colat
------ ------
0 90
20 70
45 45
-30 120
90 0
-45 135
None.
None.
W.L. Taber (JPL)
-CSPICE Version 1.0.1, 26-JUL-2016 (BVS)
Minor headers edits.
-CSPICE Version 1.0.0, 08-FEB-1998 (EDW)
spherical to latitudinal coordinates
Link to routine sphlat_c source file sphlat_c.c
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