PROXIMITY                                                             PROXIMITY



     The PROXIMITY command is summarized as follows:

          PROXIMITY is a distance analysis command that activates data from
          a map based on its proximity to some point or other map feature.
          There is also an option which allows the user to select data which
          is NOT within a specified distance.
          A typical application of the command might be to find all grassland
          which is within 0.25 miles of mule deer winter concentration range
          or to find all perennial streams which are within 5 miles of point
          X (where point X is user-specified).  The PROXIMITY command uses an
          active map(s) as input and produces a new map in the workfile as
          output.


     The PROXIMITY command is specified as follows:

        PROXIMITY (active ID's) (new map name)*(distance)*(in or not within
                   proximity )
        or

        PROXIMITY (active ID) (new map name)* (distance)* (crosshair input)*
                  (in or not within proximity)


     The individual parameters of the PROXIMITY command are described below:

          (active ID's) are the ID numbers of two maps referenced in the  
          active map table.  The first ID entered will be the origin of the
          search.  The second ID entered will be the object of the search.  The
          resultant map will be some set of features from the second map ID.
          If only one ID is entered, the resultant map will be some set of 
          features from this map which fall within a specified distance of a
          user-defined point.

          (new map name) is the name for the map which results from PROXIMITY.

          (distance) is the user-specified maximum search distance with units.
          Units may be miles (default), (K)ilometers, (F)eet, (M)eters or 
          (I)nches.  Units desired must be entered immediately after distance,
          for example, 0.25K.

          (in or not within proximity) is the user-specified  opition which
          selects all items within the specified distance or selects all of
          the items outside of the specified distance.

          (crosshair input) is where the user specifies the point origin of
          the search with the CRT cursor.


     The following is an example of use of the PROXIMITY command:

           ENTER COMMAND
          ? PROXIMITY
           Enter active map I.D.(s) to PROXIMITY ? 1 2
           What do you wish to call the new map
            __________
          ? DEERFOOD
           Enter maximum search distance (with units) ? 0.25

           Do you wish object out of proximity? [NO] (cr)

           NUMBER OF HITS =    16


     The limitations of the PROXIMITY command are as follows:

          -- Distance (tolerance) must be greater than 0.

          -- Input maps must be active and window must be set.

          -- Does not work with cell data.

          -- May not work well with large distances.

          -- No more than 1000 subjects in the new map.

          -- Subjects in new map will not be in alphabetical order.

          -- If one point of a feature is within the specified distance, the
             entire feature is considered in proximity.
