Procedure for Converting Point Data to Contour Lines and Hillshade within ArcView.

1. Create an ascii file table of x,y,z values. This can be done in Excel, or some other program, but the file needs to have the following structure:
   1. First line is a header file that delineates the fields
   2. Subsequent lines are data wherein each field is comma delimited.
   3. The first field of each data record has a unique numerical record identifier.

   Here's an example of how it might look:

          id,x,y,z
          1,101,302,555
          2,101,307,558
          etc.
   

   
   For this tutorial the file name will be called "Elev.txt".

2. Establish an ArcView project and set the working directory to where the data will be stored.
   1. Highlight the View window
   2. From ArcView's File menu, choose Set Working Directory
   3. Enter the path to where the data will be stored.

3. Activate the Spatial Analyst Extension.
   1. Highlight the Project window.
   2. From the File menu choose Extensions.
   3. Click on the check-box next to Spatial Analyst then click on OK.

4. Load data file into ArcView and create a theme.
   1. Highlight the Project window and choose Add Table from the Project menu.
      From the Add Table window navigate to the directory where your data file (table) is stored.
      Chose the proper file type under List Files of Type: (e.g., *.txt).
      Click on your file.
   2. Highlight the View window.
   3. Select Properties from the View menu.
      Enter the Map Units that the x,y coordinates in the table are in.
      Press OK.
   4. From the View menu choose Add Event Theme.
      Under Table choose Elev.txt.
      Select the x and y fields if the defaults are not correct.
      Press OK. A new point theme is added to the view.
      Display the points by checking on the box next to the theme name in the View window.
   5. From the File menu choose Save Project and save the project into the working directory. You might need to navigate to your personal directory since the default directory may not be the directory in which you want to store your data.

5. Create a "Convex Hull" (or outline) theme around the data points. This theme will be used later to control the extrapolated extent of the contour lines.
   1. Highlight the View window.
   2. Select New Theme... from the View menu.
   3. Select Polygon as the Feature Type in the New Theme window that pops up.
   4. Enter the path and name to call the new theme. (For this document the name "Convex_hull" will be used.) The new theme is added to the view and is ready to receive vertex entries. (This condition is indicated by the new theme's check box which now has a dashed outline.)
   5. Select the Draw Polygon icon. (It's one of the toolbar options. Point to the icon to the right of the "T" button, and hold down the mouse button. You will see a set of buttons from which to select. Choose the button that looks like an irregularly shaped polygon.)
   6. Add vertices to create the convex hull around the perimeter of the points by clicking on the left mouse button at the desired positions of vertices. Double click the mouse when the adding of vertices is completed. ArcView will draw a colored polygon to represent the shape you constructed.
   7. Turn off editing by selecting Stop Editing under the Theme menu.
   8. Save the project.

6. Create a table for the polygon shape file.
   1. Highlight the View window then select Table... within the Theme menu. The "Attributes of Convex_hull.shp" table is created by ArcView.
   2. With the "Attributes of Convex_hull.shp" table highlighted, select Properties under the Table menu. Check the Visible box next to ID. Press OK.
   
   Note: Be sure the Map Units parameter (e.g., meters) is assigned under View: Properties.

7. Convert the polygon to a grid.
   1. Highlight the View window, make sure the Convex_hull.shp theme is the active theme, then from the Theme menu select Convert to Grid...
   2. Under Output Grid Extent choose "Same as Elev.txt" (That is, select the name of the file from which the points were constructed. You may need to scroll down to find the file.)
   3. For Output Grid Cell Size choose 1 (for 1 meter; you can experiment with other values if desired). Use the default Number of Rows and Number of Columns values unless there is need to change those values. Press OK.
   4. In the next menu that appears you are asked to pick the field for cell values. ID should be highlighted. Press OK.
   5. In the next menu assign a directory and name for the grid (let's call it Convex_grid) that will be generated. Press OK.
   6. In the next menu select Yes for "Join feature attributes to grid?"
   7. In the next menu select Yes for "Add grid as theme to the view?"

8. Create the contours
   1. Make the point theme be the active theme.
   2. Under Analysis choose Properties.
      For Analysis Extent choose "Same as Elev.txt."
      For Analysis Cell Size choose the name for the grid theme that you just created.
      For the Analysis Mask choose the grid theme, Convex_grid. (Note: the analysis mask is important for making contours terminate at the limits of the convex hull.)
      Use the default Cell Size, Number of Rows, and Number of Columns unless you desire other values.
      Press OK.
   3. Choose Create Contours from the Analysis menu.
   4. In the Interpolate Surface window choose Spline under Method.
      Choose Z for Z Value Field (or, if different, the name of the field that contains the elevation values).
      Type in 10 for Weight and 8 for No. of Points.
      Choose Tension for Type.
      (You can experiment with other settings for each of these parameters.)
      Press OK.

      (Note: ArcView will start processing the data. You may have to wait a while at this point. In the Contour Parameters window choose 0.1 (meters) or a value you prefer for the Contour Interval. Enter the Base Contour. (This base value can be the lowest Z value in the project area.)
      Press OK. ArcView will then create the contour theme. Check the box of the theme to view the contours.

9. Interpolate Surface
   1. Highlight the point theme.
   2. From the Analysis menu choose Interpolate Surface.
   3. Fill in the menu items in the Interpolate Surface menu as was done in step 8d for the contours. ArcView will then create the Surface theme.
      Check the box of the surface theme to view the surface.

10. Derive slope
    1. Highlight the Surface theme
    2. Select Derive Slope from the Analysis menu.
       Check the box of the slope theme to view slope.

11. Derive aspect
    1. Highlight the Surface theme
    2. Select Derive Aspect from the Analysis menu.
       Check the box of the aspect theme to view aspect.

12. Compute hillshade
    1. Highlight the Surface theme
    2. Select Compute Hillshade from the Analysis menu
    3. Enter values for Azimuth and Altitude or use the default values.
       Press OK.
       Check the box of the hillshade theme to view hillshade.