pl2nvp_c |
Table of contents
Procedurepl2nvp_c ( Plane to normal vector and point ) void pl2nvp_c ( ConstSpicePlane * plane, SpiceDouble normal[3], SpiceDouble point [3] ) AbstractReturn a unit normal vector and point that define a specified plane. Required_ReadingPLANES KeywordsGEOMETRY MATH PLANE Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- plane I A SPICE plane. normal, point O A unit normal vector and point that define `plane'. Detailed_Inputplane is a SPICE plane. Detailed_Outputnormal, point are, respectively, a unit normal vector and point that define the geometric plane represented by `plane'. Let the symbol < a, b > indicate the inner product of vectors `a' and `b'; then the geometric plane is the set of vectors `x' in three-dimensional space that satisfy < x - point, normal > = 0. `point' is always the closest point in the input plane to the origin. `point' is always a non-negative scalar multiple of `normal'. ParametersNone. ExceptionsError free. 1) The input plane MUST have been created by one of the CSPICE routines nvc2pl_c ( Normal vector and constant to plane ) nvp2pl_c ( Normal vector and point to plane ) psv2pl_c ( Point and spanning vectors to plane ) Otherwise, the results of this routine are unpredictable. FilesNone. ParticularsCSPICE geometry routines that deal with planes use the `plane' data type to represent input and output planes. This data type makes the routine interfaces simpler and more uniform. The CSPICE routines that produce SPICE planes from data that define a plane are: nvc2pl_c ( Normal vector and constant to plane ) nvp2pl_c ( Normal vector and point to plane ) psv2pl_c ( Point and spanning vectors to plane ) The CSPICE routines that convert SPICE planes to data that define a plane are: pl2nvc_c ( Plane to normal vector and constant ) pl2nvp_c ( Plane to normal vector and point ) pl2psv_c ( Plane to point and spanning vectors ) Examples1) Given a plane normal and constant, find a point in the plane. `point' is the point we seek. nvc2pl_c ( normal, const, &plane ); pl2nvp_c ( &plane, normal, point ); RestrictionsNone. Literature_References[1] G. Thomas and R. Finney, "Calculus and Analytic Geometry," 7th Edition, Addison Wesley, 1988. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) Version-CSPICE Version 1.0.1, 24-AUG-2021 (JDR) Edited the header to comply with NAIF standard. -CSPICE Version 1.0.0, 05-MAR-1999 (NJB) Index_Entriesplane to normal vector and point |
Fri Dec 31 18:41:10 2021