CSPICE_NVC2PL constructs a SPICE plane from a normal vector and a constant.
For important details concerning this module's function, please refer to
the CSPICE routine nvc2pl_c.
Given:
normal a double precision 3vector
constant a double precision scalar
are, respectively, a normal vector and constant
defining a plane. 'normal' need not be a unit
vector. Let the symbol < a, b > indicate the
inner product of vectors a and b; then the
then the geometric plane is the set of vectors x
in threedimensional space that satisfy
< x, normal > = constant.
the call:
cspice_nvc2pl, normal, constant, plane
returns:
plane a structure representing the SPICE plane as
defined by 'normal' and 'constant'. The structure
has the fields:
plane.normal: [3array double]
plane.constant: [scalar double]
Any numerical results shown for this example may differ between
platforms as the results depend on the SPICE kernels used as input
and the machine specific arithmetic implementation.
;;
;; Define an arbitrary normal and constant...
;;
normal = [ 1.d, 1.d, 1.d ]
constant = 23.d
;;
;; ...then construct the SPICE plane.
;;
cspice_nvc2pl, normal, constant, plane
print, plane.constant
print, plane.normal
IDL outputs for plane.constant:
13.279056
IDL outputs for plane.normal:
0.57735027 0.57735027 0.57735027
Icy geometry routines that deal with planes use the `plane'
data type to represent input and output planes. This data type
makes the subroutine interfaces simpler and more uniform.
The Icy routines that produce SPICE planes from data that
define a plane are:
cspice_nvc2pl ( Normal vector and constant to plane )
cspice_nvp2pl ( Normal vector and point to plane )
cspice_psv2pl ( Point and spanning vectors to plane )
The Icy routines that convert SPICE planes to data that
define a plane are:
cspice_pl2nvc ( Plane to normal vector and constant )
cspice_pl2nvp ( Plane to normal vector and point )
cspice_pl2psv ( Plane to point and spanning vectors )
Any of these last three routines may be used to convert this
routine's output, 'plane', to another representation of a
geometric plane.
ICY.REQ
PLANES.REQ
Icy Version 1.0.2, 23NOV2010, EDW (JPL)
Edits to I/O section so as to parallel Mice version.
Icy Version 1.0.1, 24NOV2008, EDW (JPL)
Edited header section I/O and Particulars.
Icy Version 1.0.0, 16JUN2003, EDW (JPL)
normal vector and constant to plane
