Use this page of the Overlay Analysis dialog box to specify the information about the output layer, and to set tolerance levels for sliver polygons and the evaluation of points. Overlay results use the split rules set in the Split and Merge Rules dialog box.
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The Set Output And Settings page of the Overlay Analysis dialog box includes the following options:
- Output
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Specify the name and location of the SDF file that will contain the result of the Overlay operation.
- Layer Name
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Specify the name of the Display Manager layer that contains the result of the Overlay operation.
Sliver Tolerance
When the Overlay operation splits features to produce the output layer, it eliminates polygons that are smaller than the specified tolerance settings. Some such polygons were present in the sources, and some are produced by the Overlay operation itself. The elimination of slivers affects the output layers only.
Polygons whose areas are larger than the Maximum value become separate features in the output layer.
Polygons whose areas are smaller than the Minimum (and have at least one neighboring polygon) are considered slivers, and are merged with the neighboring polygon that has the longest shared edge.
The Overlay operation checks polygons that fall between the two values to see how wide they are. If they are very narrow, they are merged with a neighboring polygon.
- Minimum
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Specify a value in the current units. If a polygon is smaller than this value, it merges with a neighboring polygon.
- Maximum
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Specify a value in the current units. If a polygon is larger than this value, it becomes its own feature.
- Suggest
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Click to see recommendations for the Sliver Minimum and Sliver Maximum values (if they are not already displayed).
To see recommended values, click Suggest. The default suggested values for sliver tolerances are 1/10 of the smallest input area for the Maximum and 1/100 of the smallest input area for the Minimum. However, the sliver tolerance values will round down to the next power of 10. So, if the smallest polygon has an area of 50, the expected sliver tolerances should be 1 and 0.1 respectively, and not 0.5 and 5.
- Units
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Specify the units to use for the sliver Minimum and Maximum settings. The available units depend on the Source coordinate system.
- Don’t Remove Slivers
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Select this check box to have the Overlay operation ignore sliver polygons.
Ordinate Tolerance
Specify how far apart two nodes or vertices of a line or polygon must be to be treated as separate points.
- Length
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Enter a distance in the current units. Any two points that are closer together than this value are treated as a single point in the output layer.
- Units
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Specify the units to use for the Ordinate ToleranceLengthsetting. The available units depend on the Source coordinate system.
- Output Properties
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Specify which properties from the Source and (if applicable) Overlay are included in the resulting layer. “All” adds all properties to the resulting layer. “Identifiers” adds only the primary identifiers (primary keys or unique fields, such as Feature_ID). “Non-Identifiers” adds only the non-key attributes (such as Land_Value or Speed_limit, for example). If you add only non-identifiers, the overlay operation generates primary identifiers for the features in the resulting layer.