SYNOPSIS

CALL MAPTRN (RLAT, RLON, UVAL, VVAL)

C-BINDING SYNOPSIS

#include <ncarg/ncargC.h>

void c_maptrn (float rlat, float rlon, float *uval,
float *vval)

DESCRIPTION

RLAT and RLON

(input expressions, of type REAL) are the latitude and longitude, respectively, of a point on the globe. RLAT must be between -90. and +90., inclusive; RLON must be between -540. and +540., inclusive.

UVAL and VVAL

(output variables, of type REAL) define the point (UVAL,VVAL) that is the projection in the u/v plane of (RLAT,RLON). The units of UVAL and VVAL depend on the projection.

If the point is not projectable, UVAL is returned equal to 1.E12. If the point is projectable, but outside the boundary of the map (as defined by the last call to MAPSET and by the value of the parameter 'EL'), the routine MAPTRN, unlike MAPTRA, still returns its u and v coordinates.

C-BINDING DESCRIPTION

The C-binding argument descriptions are the same as the FORTRAN argument descriptions.

EXAMPLES

Use the ncargex command to see the following relevant examples: cpex03, mpex09.

ACCESS

To use MAPTRN or c_maptrn, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c, preferably in that order.

MESSAGES

See the ezmap man page for a description of all EZMAP error messages and/or informational messages.

COPYRIGHT

Copyright (C) 1987-2009
University Corporation for Atmospheric Research
The use of this Software is governed by a License Agreement.