1MAPGCI(3NCARG) NCAR GRAPHICS MAPGCI(3NCARG)
2
6 MAPGCI - Returns a set of points on the shortest great circle route
7 between two user-specified points on the globe.
8
10 CALL MAPGCI(ALAT,ALON,BLAT,BLON,NOPI,RLTI,RLNI)
11
13 #include <ncarg/ncargC.h>
14 void c_mapgci( float alat, float alon, float blat,
16 float blon, int nopi, float *rlti, float *rlni)
17
19 ALAT and ALON
20 (input expressions, of type REAL) are the latitude and
21 longitude of the point at the beginning of a great circle
22 route.
23 BLAT and BLON
25 (input expressions, of type REAL) are the latitude and
26 longitude of the point at the end of a great circle route.
27 NOPI (an input expression, of type INTEGER) is the number of
29 equally-spaced points to be interpolated along the great
30 circle route.
31 RLTI and RLNI
33 (output arrays of type REAL, each dimensioned at least
34 NOPI) are arrays containing the latitudes and longitudes of
35 points interpolated along the great circle route. Each
36 lat/lon pair defines one of the points; they appear in
37 order of increasing distance along the great circle route.
38 The positions of the first point and the last point are not
39 returned in these arrays; only the interpolated points are.
40
42 The C-binding argument descriptions are the same as the FORTRAN
43 argument descriptions.
44
46 The statement:
47 CALL MAPGCI (ALAT,ALON,BLAT,BLON,NOPI,RLTI,RLNI)
49 defines the positions of two points, A and B, on the globe and the
51 number of equally-spaced points, NOPI, to be interpolated along the
52 great circle route from A to B. The latitudes and longitudes of the
53 interpolated points are returned to the caller in the arrays RLTI and
54 RLNI. If the points A and B are exactly opposite one another on the
55 globe, the code does not fail, but the direction of the great circle
56 route will be somewhat unpredictable (since, in that case, there is
57 more than one great circle route joining the two points).
58
60 Use the ncargex command to see the following relevant example: cmpgci.
61
63 To use MAPGCI or c_mapgci, load the NCAR Graphics libraries ncarg,
64 ncarg_gks, and ncarg_c, preferably in that order.
65
67 Online: ezmap, ezmap_params, mapaci, mapbla, mapblm, mapdrw, mapeod,
68 mapfst, mapgrd, mapgrm, mapgtc, mapgti, mapgtl, mapgtr, mapint, mapiq,
69 mapiqa, mapiqd, mapiqm, mapit, mapita, mapitd, mapitm, maplbl, maplmb,
70 maplot, mappos, maproj, maprs, maprst, mapsav, mapset, mapstc, mapsti,
71 mapstl, mapstr, maptra, maptri, maptrn, mapusr, mapvec, mpchln, mpfnme,
72 mpgetc, mpgeti, mpgetl, mpgetr, mpglty, mpiaty, mpifnb, mpilnb, mpiola,
73 mpiosa, mpipai, mpipan, mpipar, mpisci, mplnam, mplndm, mplndr, mplnri,
74 mpname, mprset, mpsetc, mpseti, mpsetl, mpsetr, supmap, supcon,
75 ncarg_cbind
76 Hardcopy: NCAR Graphics Contouring and Mapping Tutorial
78
80 Copyright (C) 1987-2007
81 University Corporation for Atmospheric Research
82 This documentation is free software; you can redistribute it and/or
84 modify it under the terms of the GNU General Public License as
85 published by the Free Software Foundation; either version 2 of the
86 License, or (at your option) any later version.
87 This software is distributed in the hope that it will be useful, but
89 WITHOUT ANY WARRANTY; without even the implied warranty of
90 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
91 General Public License for more details.
92 You should have received a copy of the GNU General Public License along
94 with this software; if not, write to the Free Software Foundation,
95 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
96UNIX March 1993 MAPGCI(3NCARG)