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d.where

Identifies the geographic coordinates associated with point locations given in display coordinates.

d.where [-dlwf] [at=x,y [,x,y,...]] [input=name] [--verbose] [--quiet] [--qq] [--ui]

Example:

d.where

grass.script.run_command("d.where", at=None, input=None, flags=None, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("d.where")

Parameters

at=x,y [,x,y,...]
    Display coordinates to convert
input=name
    File from which to read coordinates ("-" to read from stdin)
-d
    Output lat/long in decimal degree
-l
    Output lat/long referenced to current ellipsoid
-w
    Output lat/long referenced to WGS84 ellipsoid using datum transformation parameters defined in current location (if available)
-f
    Output frame coordinates of current display monitor (percentage)
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

at : list[tuple[float, float]] | tuple[float, float] | list[float] | str, optional
    Display coordinates to convert
    Used as: x,y
input : str, optional
    File from which to read coordinates ("-" to read from stdin)
    Used as: input, file, name
flags : str, optional
    Allowed values: d, l, w, f
    d
        Output lat/long in decimal degree
    l
        Output lat/long referenced to current ellipsoid
    w
        Output lat/long referenced to WGS84 ellipsoid using datum transformation parameters defined in current location (if available)
    f
        Output frame coordinates of current display monitor (percentage)
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

d.where is an interactive program that allows the user, using the pointing device (mouse), to identify the geographic coordinates associated with point locations within the current geographic region in the active display frame on the graphics monitor.

Each mouse click will output the easting and northing of the point currently located beneath the mouse pointer. A mouse-button menu is presented so the user knows which mouse buttons to use. The output is always printed to the terminal screen; if the output is redirected into a file, it will be written to the file as well.

Mouse buttons:

     Left:   where am i
     Middle: draw to/from here
     Right:  quit this

The left mouse button prints the coordinates at the selected point, the middle mouse button allows you to query two points (they are connected by a line for convenience). Use the right mouse button to exit the module.

NOTES

This program uses the current geographic region setting and active frame. It is not necessary, although useful, to have displayed a map in the current frame before running d.where. The -d flag allows the user to optionally output latitude/longitude coordinates pair(s) in decimal degree rather than DD:MM:SS format. The -w flag is only valid if a datum is defined for the current project's coordinate reference system. If the -f flag is given the x,y frame coordinates of the active display monitor will be returned (as a percentage, 0,0 is bottom left).

EXAMPLE

Query position in map (North Carolina sample dataset):

d.rast elevation
d.where

SEE ALSO

d.what.rast, d.what.vect, g.region, v.what.rast, v.what.vect

AUTHORS

James Westervelt,
Michael Shapiro,
U.S. Army Construction Engineering Research Laboratory

SOURCE CODE

Available at: d.where source code (history)
Latest change: Friday Feb 07 19:16:09 2025 in commit a82a39f