Provided by: libncarg-dev_6.6.2.dfsg.1-10build2_amd64 bug

NAME
       c_shgetnp - find the nearest points to a specified point in 3-space


FUNCTION PROTOTYPE
       int c_shgetnp(float, float, float, int, float *, float *, float *,
                     int, int *);


SYNOPSIS
       int c_shgetnp (px, py, pz, n, x[], y[], z[], iflag, ier );


DESCRIPTION
       px          (float) The X coordinate value for a point P whose nearest neighbor is to be found.

       py          (float) The Y coordinate value for a point P whose nearest neighbor is to be found.

       pz          (float) The Z coordinate value for a point P whose nearest neighbor is to be found.

       n           (int) The number of input data points, n > 1.

       x           (float) An array of length n containing the X coordinate values for the input data points.

       y           (float) An array of length n containing the Y coordinate values for the input data points.

       z           (float) An array of length n containing the Z coordinate values for the input data points.

       iflag       (int) A flag that equals 0 if this is the first call to this subroutine for the given dataset
                   and equals 1 otherwise.

       ier         (pointer  to  int)  An  error  return  value.   If *ier is returned as 0, then no errors were
                   detected. If *ier is non-zero, then look at the man page for shgrid_errors for details.


USAGE
       c_shgetnp is called to find the nearest point to a  specified  point  in  3-space.  Successive  calls  to
       c_shgetnp  will determine the point nearest the specified point exclusive of the points found in previous
       calls, i.e. successive calls can be used to find the N nearest points for  any  N  between  one  and  the
       maximum number of points in the input dataset.

       c_shgetnp returns an integer, say np, such that (x[np],y[np],z[np]) is the nearest input data point to P.
       np  = -1 if *ier is not zero. On successive calls to this function after the first (that is when iflag=1)
       you can find the Mth closest point to (px,py,pz) with the Mth call.


ACCESS
       To use c_shgetnp, load the NCAR Graphics library ngmath.


SEE ALSO
       shgetnp, c_shgrid, c_shseti, c_shgeti, shgrid_params.

       Complete documentation for Sh is available at URL
       http://ngwww.ucar.edu/ngdoc/ng/ngmath/shgrid/shhome.html


COPYRIGHT
       Copyright (C) 2000
       University Corporation for Atmospheric Research

       The use of this Software is governed by a License Agreement.

UNIX                                              January 1999                                 c_shgetnp(3NCARG)