Selection Sets


Selection sets are used to select subsets of a layer’s features. These are a very powerful capability in Maptitude, and are controlled from the Selection toolbar:

The Selection toolbar

The Selection toolbar

The current selection set is listed in the first drop-down box (Selection in this example) and is followed by the number of features selected in the set (125 in this example). A data field can be summed for all features in this set. This field is selected in the second drop-down box, and the sum is displayed to the right of it. In this example, ccStyle has been selected and the sum is 3626. This is a bit meaningless for ccStyle but is useful for attributes such as population, sales, etc.

A new selection set is created by pressing the Create button (funnel with a green ‘+’). It can be deleted by pressing the Delete button (funnel with a red ‘x’).

The five buttons to the left are used to select features. The first four create a selection set using a mouse tool, whilst the fifth (funnel with fx) creates a selection set with an attribute condition. You can also create selection sets by area feature adjacency, and by location.

Selection set names and themes can be modified by using the Selection Sets dialog box. This is displayed by pressing the Selection Settings button (funnel on a window), and looks like this:

The Selection Sets dialog box

The Selection Sets dialog box

This dialog box lists all available selection sets, including the global set (i.e. all layer features). Select one of these sets, and then press the button to modify it. The Status button is used to make a set active, inactive, or invisible. It is very easy and useful to create lots of selection sets, but this can become difficult to manage. Hence you may wish to make some of the sets inactive or invisible. You can also show or hide a selection set using the Display Manager.

Use Add Set and Drop Set to create or delete a selection set. Use Clear Set to remove all features from a selection set without deleting it.

The default name for a selection set is Selection. Use the Rename button to give a more appropriate name to a new selection set. Use the Style and Labels buttons to modify the map styling for a specific selection set. For example, selected features are often drawn in red so that they can be distinguished from the other features. The current selection set’s style can also be modified by pressing the Change style button (funnel with palette) on the Selection toolbar.

Selection behavior is controlled with the Selection Options dialog box:

Selection Options dialog box

Selection Options dialog box

This is displayed by pressing the Options button (funnel with gear). Most of these options are self explanatory. Use the When Selecting Area Features options to determine if a feature can be in multiple selection sets or not. Use the Select Features that are options to control how features selected by a surrounding shape (e.g. rectangle or circle) are selected if only part of the features are in the surrounding shape. The Hold the shift key checkbox is an optional  short cut when selecting new features to be added to a selection set.

The Optional Tools control the tools that appear on the right half of the Selection toolbar. The above image shows the running totals. You can also display a set of forward/backward navigation buttons that let you browse through the individual features in the selection set. As you navigate the selection set, Maptitude will zoom to the current feature in the selection set.

Finally you can manipulate selection sets using set algebra operations. These operations include the ability to combine selection sets, find common features, and remove one set of features from a second set.

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