How to classify the dot grid:
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To start classifying the DG, verify that the DG feature class is loaded in the table of contents (TOC) and visible (Figure 3). If the feature class is not loaded, press the "Load Dot Grid" button on the RLCM tool bar (Figure 1, Item 2). Next, select a time period to classify; for more information see "Manage Time Periods Tool". Last, load images to interpret that fall within the selected time period and spatial extent of the study area. To load the images, use ArcMap's Add Data  button. The only requirement is that the images
selected have a record in the image library. If the images do not have a record, no classification
can be applied to the DGs falling on those images.
Once the DG feature class and valid image(s) are added in the TOC, the user can begin the land cover classification. Use a systematic approach to classify the study area. For example, a common approach is to first determine the appropriate scale to make an interpretation, then move through the study area at that scale from west to east. Choose a logical starting location in the study area, move to that location, then set the view to the appropriate scale within ArcMap's active data frame or viewing window. Once the extent and scale are set, initiate the classification tool called the "Attributer" by pressing either the "Dot Grid Attributer" button (Figure 1, Item 6) or one of the DG selection tools (Figure 1, Items 7 and 8). This will open a floating dialog window showing the list of the classes selected during the initial study area dialog. With the Attributer open, choose a DG selection tool, either exclusive (Figure 1, Item 7) or inclusive (Figure 1, Item 8). With a selection tool select DGs with the same land cover class by clicking and dragging the cursor over the points. Once there is a collection of DGs selected with a common class type, choose that class from the Attributer dialog window. To commit that class attribute to the collection, either double click on the class type or choose the class type from the list and press the Save Attribute button located in the lower right of the Attributer dialog window. RLCM then validates that each dot is on an image from the library, then stores the classification attribute along with the image used to make the classification, date attributed and study area. An efficient method for classifying a viewing window is determine the most common class in the window, select all the points within it, apply that class, and clear the selection using the clear selection button (Figure 1, Item 9) then systematically move through the window reclassifying all the DGs deviating from that common class. Continue with this approach throughout the study area until it is completely attributed. To classify this same study area for a different time period, simply add another time period by pressing the Manage Time Period button (Figure 1, Item 4). Once a new time period has been added, select it from the Time Period pull-down menu (Figure 1, Item 5) and follow the same approach as the pervious period. |
 Figure 3: ArcMap Table of Contents |