NAME

       ARGTAI - Returns the area identifiers associated with a given point.

SYNOPSIS

       CALL ARGTAI (MAP,XCD,YCD,IAI,IAG,MAI,NAI,ICF)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_argtai (int *map, float xcd, float ycd, int *iai, int *iag, int mai, int *nai, int
       icf)

DESCRIPTION

       MAP         (an input/output array of type INTEGER) - An array containing an area map that
                   has been initialized by a call to ARINAM and to which edges have been added by
                   calls to AREDAM.  If you did not preprocess the area map by calling ARPRAM,
                   ARGTAI calls it before doing anything else.

                   Note: As part of initializing the area map, ARINAM stores the dimension of MAP
                   in MAP(1); therefore, the dimension does not have to be given as an argument
                   in calls to ARGTAI.)

       XCD         (an input expression of type REAL) - The X coordinate, in the current user
                   coordinate system, of a point about which you want to obtain information.

       YCD         (an input expression of type REAL) - The Y coordinate, in the current user
                   coordinate system, of a point about which you want to obtain information.

       IAI         (an output array, dimensioned MAI, of type INTEGER) - The array in which area
                   identifiers for the area containing the specified point will be returned.

       IAG         (an output array, dimensioned MAI, of type INTEGER) - The array in which group
                   identifiers for the area containing the specified point will be returned.

       MAI         (an input expression of type INTEGER) - Dimension of each of the arrays IAI
                   and IAG. MAI must be greater than or equal to NAI.

       NAI         (an output expression of type INTEGER) - The number of values returned in IAI
                   and IAG. NAI equals the number of groups of edges that you put in the area
                   map.

       ICF         (an input expression of type INTEGER) - Flag set nonzero by you to indicate
                   that the definition of the user coordinate system has been changed since the
                   last call to ARGTAI; in this case, calls to GETSET must be executed by ARGTAI.
                   If you set the flag to zero, Areas assumes that the information retrieved
                   previously is still correct and skips calls to GETSET. This option is valuable
                   if you are planning to make thousands of calls to ARGTAI with the same area
                   map: do the first one with ICF = 1 and the rest with ICF = 0.

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: carfill, carline, carmap,
       cbex01, tareas, fsppoint.

ACCESS

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

MESSAGES

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

SEE ALSO

       Online: areas, areas_params, ardbpa, ardrln, aredam, argeti, argetr, arinam, armvam,
       arpram, arscam, arseti, arsetr, ncarg_cbind

       Hardcopy: NCAR Graphics Contouring and Mapping Tutorial

COPYRIGHT

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