The Third Spatial Dimension - Introducing Geographic Information Systems with ArcGIS - page 552

sort, you may not want to do it this way (or you may), but the main idea here is for you to learn by being
exposed to several methods.
40. Start a new map in ArcMap, without saving the changes. From
___ IGIS-Arc_ YourInitials \Elevation_Data\The_Dig
add as data the table Mt_P.txt. Open the table to be sure you have a 180-record table, with
headings of Point, Northing, Easting, X, Y, H, and Elev_MSL. Close the table.
41. Using Search find the Kriging (3D Analyst) tool in ArcToolbox. Where is the tool? _____________
_______________________ Double-click the tool name to start the tool.
42. In the Kriging window, for Input point features, browse to
___ IGIS-Arc_ YourInitials \Elevation_Data\The_Dig
and click OK. (You may be able just to pick up Mt_P.txt Events from the drop-down menu.)
Otherwise, navigate to
___ IGIS-Arc_ YourInitials \Elevation_Data\The_Dig
to get the events table. For the Z value field use Elev_MSL. Accept the Output surface raster
name—something like Kriging_Site1. The raster should go into
___ IGIS-Arc_ YourInitials \Elevation_Data\The_Dig\Mount_Paolo.gdb.
While we could change a lot of the parameters on the Kriging window, we would probably need
a statistician to tell us what the various options are. We will accept the default values, except
for the cell size. Since we are dealing with a small area we can afford to make the cell size tiny.
We'll use one-tenth of a meter.
43. For Output cell size type 0.1. Click OK. Wait. When Kriging_Site1 is added to the map, click
Close.
44. Examine the raster. Use the Identify tool to look at some elevations. Zoom in to one of the
higher areas of the map. You will notice the lack of “stair steps” that usually accompany
rasters or grids. This is because the Layer Properties (Display tab) is set to show continuous
data. To see the actual DEM cells, you can “Resample during display using” Nearest Neighbor
(for discrete data) and zooming in. Measure the side of a DEM cell in meters. _________ If you
want to see a table of the DEM, however, you are out of luck. Kriging creates a “continuous”
surface, which has no attribute table because of the large number of possible values.
Add Site_TIN to the map. Experiment by looking at the elevations of each feature class. Click on
the Display tab. Make sure the TIN is the first entry in the Table of Contents. In the Properties
window (Display tab) of the Kriging site show MapTips. Then use the Identify tool on the TIN and
compare the identified value with the map tip value.