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       d.what.rast   -  Allows  the user to interactively query the category contents of multiple
       raster map layers at user specified locations within the current geographic region.


       display, raster


       d.what.rast help
       d.what.rast [-1tc] map=name[,name,...]  [fs=character]   [--verbose]  [--quiet]

           Identify just one location

           Terse output. For parsing by programs

           Print out col/row for the entire map in grid resolution of the region

           Verbose module output

           Quiet module output

           Name of existing raster map(s)

           Field separator (terse mode only)
           Default: :


       d.what.rast outputs the category values  and  labels  associated  with  cell(s)  at  user-
       specified location(s) on user-named raster map layer(s).

       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.


       Mouse  button return values are as follows: 0 indicates no button was pressed, 1 indicates
       that the left mouse button was pressed, 2 indicates the middle button was pressed,  and  3
       indicates that the right mouse button was pressed.

       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:

       d.what.rast map=soils,aspect > what.out

       will  both  send d.what.rast output to the screen and capture its output in the file named

       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.


       It  is  helpful, but not necessary, to first display a map to be used for reference in the
       active display frame before running d.what.rast.  For example, the  user  might  type  the
       following series of commands and receive the output below.

       d.rast map=soils

       To first display the soils map in the active frame.

       d.what.rast map=soils,aspect

       User  then  moves  the  mouse  to  desired  location on the displayed soils map layer, and
       presses the left mouse button to query the category contents of the soils and aspect  maps
       at this geographic location.  The program then outputs the below information to the user's

       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

       d.what.rast -t map=soils,aspect

        produces  output  in  the  form  shown below. The first line of output gives the easting,
       northing, and the mouse button return value (see NOTES below).  Each subsequent line gives
       the map name and its mapset, the category value, and category label of the point specified
       on the user-named raster map layers.  The default output field separator, a colon, is used
       since none was specified on the command line.

       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.




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

       Last changed: $Date: 2013-04-13 03:41:41 -0700 (Sat, 13 Apr 2013) $

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