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MAPublisher Dot Density Maps

Dot density themes are sometimes called dot distribution maps because they show where particular data characteristics occur. It uses dots or other symbols to represent the number of occurrences of a given data characteristic in a particular location. Starting at MAPublisher 8.4, the ability to create dot density maps is available through the provision of Dot Density Themes.

When creating a new MAP Theme simply choose “Dot Density” from the available theme types. The creation of a dot density theme is facilitated through the MAP Themes panel. The dot density theme is an Adobe Illustrator effect applied to an area layer.

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As dot density maps are most useful for showing where particular data occur, they may only be generated for MAP Area type layers. Most often, symbols are used to represent data occurring within a bounding polygon such as a census tract, zip code or county polygons.

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Dot density effects are created on a per layer basis, based on various user defined settings. Data ranges can be determined from selected attribute columns and then a dot value can be assigned a corresponding symbol at which point MAPublisher will map the appropriate results. Users may apply default symbols or load custom ones based on Illustrator symbol sets

In this example, population tallies per county have been loaded, assigned a dot value of 10,000 with a designated symbol of a 2pt black dot.

This screenshot displays the map prior to applying the dot density effect.

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The screenshot below displays the map after having applied the Dot Density Theme using the parameters displayed within the dialog .

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Using Make Index for Geoprocessing in MAPublisher 8.4.2

New to the MAPublisher 8.4.2 Make Index tool is an enhancement that allows you to index objects relative to a MAP Area layer’s features instead of an index grid. This new functionality compliments the existing geoprocessing tools found in the Buffer Art tool and the Spatial Filter in the MAP Selections panel.

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An index grid on a MAP Legend layer is no longer a prerequisite for using the Make Index tool. By choosing the “Use Area layer as grid” option in the Make Index dialog box, a spatial query will be performed and an index file will be produced based on the layer and attribute specified.

For this example, I have loaded a point file of cities and a point file of nuclear facilities against a background of North America. I then proceeded to use the Buffer art tool to create 80 kilometer buffers around each facility.

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Finally, I will produce an index that returns which communities fall within the 80 km radius surrounding each nuclear facility. For this index I will choose my Towns_labels MAP Text layer.

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With these settings our index gives a line for each city that falls within the buffer, and after a tab delimiter, gives the name of each facility as found in the kmlName attribute of the Buffered Art layer. Notice that for cities that fall within the buffer of multiple nuclear facilities, the values from the kmlName attribute field are concatenated together with a semicolon “;”.

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If you choose to make an index using an index grid, the option to add an attribute from a bounding MAP Area layer can be accessed from the Advanced tab of the Make Index dialog.