How to digitize, project, and attribute map features using ArcInfo

1. In UNIX, edit a new file, let's call it malibu.geo, and type in the longitude and latitude coordinates of the four corners of the map starting from the upper left corner and then progressing around the map in a clockwise manner.

   Apply the following constraints:

   • Enter the degrees, then minutes, then seconds for each longitude value and latitude value.
   • Enter the longitude value first then the latitude value.
   • Be sure to add a minus sign in front of the longitude value (for Western Hemisphere maps). Also, separate the fields with spaces. Never use TABs in a table that ArcInfo will read.
   
   The following is an example of how the file should appear.

            -118 45 00  34 07 30
            -118 37 30  34 07 30
            -118 37 30  34 00 00
            -118 45 00  34 00 00
         

   
   

2. Construct a projection-parameters file (call it geo_to_spz7.prj). The following is an example of a file that will be used to project the file from geographic (i.e., longitude/latitude) to State Plane Zone 7:

            INPUT 
            PROJECTION GEOGRAPHIC
            UNITS DMS
            DATUM NAD27
            PARAMETERS
            OUTPUT
            PROJECTION STATEPLANE
            UNITS FEET
            ZONE 3426
            DATUM NAD27
            PARAMETERS
            END
         

   
   

3. In ArcInfo, project the geographic coordinates in the malibu.geo file to a new file (malibu.sp) where the output coordinates will be stored in State Plane coordinates.

            Arc: project file malibu.geo malibu.sp geo_to_spz7.prj
         

   
   The resulting file looks like this:

            4060585.5234        4158151.5010
            4098417.5154        4158020.2517
            4098287.5537        4112532.0241
            4060399.8641        4112663.4666
         

   
   

4. In UNIX, edit the malibu.sp file and add the integers 1, 2, 3, and 4 in front of the longitude/latitude pairs. (The integers will be used to identify tics in the coverage that is to be generated. Again, don't use TABs to separate the data fields.) Then add the word "end" to the end of the file as such:

            1    4060585.5234        4158151.5010
            2    4098417.5154        4158020.2517
            3    4098287.5537        4112532.0241
            4    4060399.8641        4112663.4666
            end
         

   
   

5. In ArcInfo, generate a coverage (called malibu) using the projected file. The resulting coverage will have tics with the same coordinates as those in the malibu.sp file:

            Arc: generate malibu
            Generate: input malibu.sp
            Generate: tics
            Generate: quit
         

   
   To see the resulting tic values in the coverage list them out.

            Arc: list malibu.tic
            Record  IDTIC         XTIC         YTIC
                 1      1  4060585.500  4158151.500
                 2      4  4060399.750  4112663.500
                 3      2  4098417.500  4158020.250
                 4      3  4098287.500  4112532.000
         

   
   

6. Develop a point-attribute table (PAT) for the new malibu coverage using the BUILD command. (The table is identified by the name of the coverage followed by ".pat".) BUILD also adds point topology to the malibu coverage.

            Arc: build malibu points
         

   
   

7. Add attributes (items) to the point coverage (if desired). The attributes get added to the PAT. For this operation, name the output PAT the same as the input PAT (i.e., malibu.pat). Define your own name for the attribute to add (e.g., my_att_name), and the size (bytes) and type of attribute.

            Arc: additem malibu.pat malibu.pat my_att_name 4 4 C
         

   
   To see the resulting PAT items type the following:

            Arc: items malibu.pat
            COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME     INDEXED?
                1  AREA                   4    12     F      3                        -
                5  PERIMETER              4    12     F      3                        -
                9  MALIBU#                4     5     B      -                        -
               13  MALIBU-ID              4     5     B      -                        -
               17  MY_ATT_NAME            4     4     C      -                        -
         

   
   

8. Mount the map to be digitized on the digitizing board. Secure the map tightly to the surface with tape at each corner.

9. Turn on the digitizer switch.

10. In ArcInfo, start up ARCEDIT.

             Arc: arcedit
          

    
    

11. The digitizer is connected to the Ultra 10 "mono". There is a local program (specifically an ArcInfo AML) that you must run which sets up the digitizing environment. To do this, in ARCEDIT, type:

             Arcedit: setdig 
          

    
    This last command will define parameters used to communicate with the digitizer. It also sets the ArcInfo coordinate environment (i.e., the method for entering data) to the mouse. (Other coordiante options are the digitizer and keyboard.)

12. Digitize the tics for the current (projected) map:

             Arcedit: coordinate digitizer malibu
          

    When you enter this command you will be prompted to digitize four tics. The prompt looks like this:

             Digitize a minimum of 4 tics.
             Signal end of tic input with Tic-ID = 0
             Tic-ID:
          

    Digitize the corners of the map in the same order as their associated coordinates appear in the malibu.sp file (i.e., upper-left, upper-right, lower-right, then lower-left). To digitize tics, using the digitizer puck press the "1" button (this will indicate the tic number - in this case tic #1), then the "A" button, then move the cross hairs directly over the #1 tic on the map and press the "1" button to signal the desired tic location. Do this procedure for each of the three other tics:

             button 2 , button A , line up tic #2, button 1
             button 3 , button A , line up tic #3, button 1
             button 4 , button A , line up tic #4, button 1
          

    Then press the "0" button and the "A" button. That will terminate the process of establishing tic locations. The screen should show the following entries.

             Tic-ID: 1*
             Tic-ID: 2*
             Tic-ID: 3*
             Tic-ID: 4*
             Tic-ID: 0*
          

    If you make a mistake in tic entry, simply issue the "coordinate digitizer malibu" command and follow the tic-entry instructions again.

    
    

13. Establish the editing environment for the malibu coverage.

             Arcedit: editcov malibu
             Arcedit: drawen tic label
             Arcedit: draw
          

    
    

14. Begin adding labels to the coverage. (Use the "1" key on the puck to add label points; use the "9" key, while the puck is held on the digitizing board, when finished digitizing points.)

             Arcedit: editf label
             0 element(s) for edit feature LABEL
             Arcedit: add
          

    
    This would be a good time to save your work.

             Arcedit: save
          

    
    

15. If desired, select specific label features and add information to their attributes.

             Arcedit: select *
             Arcedit: moveitem "abc" my_att_name
          

    
    

16. Once you are done adding label features and attribute values, make the transition from the digitizer back to the mouse as the input device.

             Arcedit: coord mouse
          

    
    

17. Save your work and exit ARCEDIT.

             Arcedit: save
             Arcedit: q