The program will query the contents of raster map layer(s) named by the user on the command line. These map layers must exist in the user's current mapset search path. If the user does not name any raster map layers on the command line, d.what.rast will query the category contents of whatever raster map layer is already displayed in the active frame on the graphics monitor.
The program activates the mouse, and expects the user to indicate the cell location(s) to be queried by depressing a mouse button over desired location(s) within the current geographic region in the active display frame on the graphic monitor.
617112(E) 3732014(N) soils in PERMANENT (44)Nunn clay loam, NdC aspect in PERMANENT (20)15 degrees north of west
The first line of output gives the easting (E) and northing (N) coordinates of the geographic location at which the user clicked the mouse. Subsequent lines give the selected map(s) name and mapset, map category value (within parentheses), and map category label corresponding to this user-selected map location.
The query may be repeated as often as desired using the left mouse button. The right button on the mouse is used to quit the d.what.rast session.
Users can set the -t flag to obtain a terse output from d.what.rast. This is useful when the user wishes output to be parsed by another program (like awk). If the -t flag is set, users can also select the field separator used (with the fs=name option), or elect to use the default : field separator. In this case, the command
617112:3732014:1 soils@PERMANENT:44:Nunn clay loam, NdC aspect@PERMANENT:20:15 degrees north of west
Users can also use this program inside of shell scripts that require as input a map category value and a mouse button depressed. Users can choose an option to run d.what.rast only once, and return only the map category value found and the number of the mouse button depressed.
d.what.rast will always print its output to the terminal screen. d.what.rast output can be redirected into a file; however, if it is, the output will go both to the screen and to the file. For example:
The maximum number of raster map layers that can be queried at one time is 15.
d.what.vect allows the user to interactively query the category contents of multiple vector map layers at user-specified locations.
Last changed: $Date: 2004-08-05 05:53:21 -0700 (Thu, 05 Aug 2004) $
Main index - display index - Full index
© 2003-2008 GRASS Development Team