void latcyl_c ( SpiceDouble radius,
SpiceDouble lon,
SpiceDouble lat,
SpiceDouble * r,
SpiceDouble * lonc,
SpiceDouble * z )
Convert from latitudinal coordinates to cylindrical coordinates.
None.
CONVERSION, COORDINATES
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
radius I Distance of a point from the origin.
lon I Angle of the point from the XZ plane in radians.
lat I Angle of the point from the XY plane in radians.
r O Distance of the point from the z axis.
lonc O Angle of the point from the XZ plane in radians.
z O Height of the point above the XY plane.
radius Distance of a point from the origin.
lon Angle of the point from the XZ plane in radians.
lat Angle of the point from the XY plane in radians.
r Distance of the point from the z axis.
lonc Angle of the point from the XZ plane in radians.
`lonc' is set equal to `lon'.
z Height of the point above the XY plane.
None.
Error free.
None.
This routine returns the cylindrical coordinates of a point
whose position is input in latitudinal 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.
Other than the obvious conversion between coordinate systems
this routine could be used to obtain the axial projection
from a sphere to a cylinder about the z-axis that contains
the equator of the sphere. The following code fragment
illustrates this idea.
latcyl_c ( radius, lon, lat, &r, &lon, &z );
r = radius;
r, lon, and z now contain the coordinates of the projected
point. Such a projection is valuable because it preserves the
areas between regions on the sphere and their projections to the
cylinder.
None.
None.
E.D. Wright (JPL)
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)
latitudinal to cylindrical coordinates
Link to routine latcyl_c source file latcyl_c.c
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