Average Overlay

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The Average Overlay of the urbanization attribute.

The Average Overlay is a multi purpose Grid Overlay which displays (smoothed) values. These values can originate from spatial features, such as buildings, terrains, areas and neighborhoods. Alternatively, the values can originate from an other Grid Overlay.

A parameter assigned to a grid-cell can be related to one or more types of features in the project area: Buildings, Addresses, Terrains, Areas, Neighborhoods and Net Lines.

Thirdly the Average overlay supports replacing NO_DATA values with interpolated non NO_DATA values using surrounding cells within a specified distance.

Additional information displayed in hover panel

The Average Overlay of the urbanization attribute and additional information in the hover panel.

When clicking on a specific location in the map of the Average Overlay, the hover panel gives additional information over the actual value in that specific grid cell.

Calculation

The Average Overlay works by first rasterizing input values. These values can be obtained from Vector data or a Grid Overlay.

Once rasterized, the configured result type determines the operation applied on these values.

Additional parameters determine for example the range of the operation, the default value in case none was rasterized and the amount of timeframes that should be created when rasterizing an attribute with potentially more than one value.

Averaged Input Type

You can also configure in what way a value for this overlay will be rasterized:

  • First: Selects the first value encountered among all considered Vector data types. See Rasterized Vector data for the order.
  • Min: Selects the minimum value among all considered Vector data types.
  • Max: Selects the maximum value among all considered Vector data types.
  • Single layer: Only Vector data of the configured MapLink (Average Overlay) is rasterized.
  • Grid: Use the values of another Grid Overlay when specified as input, instead of an Attribute. NO_DATA values of the referenced Overlay result in NO_DATA values in the grid. The Average Overlay will have timeframes equal to the amount of timeframes of the Input Overlay. In case the input Grid Overlay does not have the same grid size as the Average Overlay, the input Grid Overlay 's value grid is automatically resized.


Average Result Type

The configured Average Overlay result type determines how a cells value is calculated. The following result types are supported for the Average Overlay:

Rasterized Vector data

The Vector data that is rasterized is determined by two values: the configured layer MapLink (Average Overlay) of the Average overlay and the configured Average Type. If the Average Type is set to Grid, no vector data is rasterized for this overlay. When the MapLink is set to null, and the Average Type is set to anything other than Grid, all MapLink layers are considered. When the MapLink layer is set to a specific MapLink, only that type of data is rasterized.

The Average Overlay currently supports the following MapLinks (in order): Net Lines, Addresses, Buildings, Terrains, Areas, Neighborhoods.

Calculation

The way of averaging is defined by several Attributes, and can most easily be set using the Average Overlay Wizard.

The calculation can be configured via the following attributes: