Function Description
Surface aggregation is to merge the surface features within the specified distance into a new surface feature to obtain the aggregated surface feature Dataset.
Application scenario
Common application scenarios, such as the need to obtain the degree of aggregation of rural residential land, generally require such indicators as continuity to determine. Continuity refers to the aggregation of plots or houses within a certain range into a patch. For example, the aggregation distance of plots of construction land is 100 meters, that is, each plot to be aggregated is buffered by 100 meters, and all plots within the range are aggregated.
Different aggregation-defined distances produce different effects, as shown in the following figure:
If you want to exclude some independent broken surfaces in the data, you can set the limited area in the Parameters, as shown in the following figure:
Sometimes, void surfaces (holes) may appear in the results. In this case, the hole limit area in Set Parameters can be eliminated, as shown in the following figure:
Function entrance
- Data tab-> Data Processing-> Vector-> Face Aggregation.
- Toolbox-> Data Processing-> Vector-> Face Aggregation.
Parameter Description
- Source Data: Set the Dataset to be processed and the Datasource where it is located. Dataset must be a faceted Dataset.
- Aggregation Limit Distance: Set the distance to be met between face feature boundaries when aggregating, that is, aggregation can only occur at a position where two face feature boundaries are within the specified aggregation distance. The value range is greater than 0.
- Unit: Set the unit of aggregation limit distance. The default is meter for Planar Coordinate System and Projected Coordinate System, and degree for Geographic Coordinate System.
- Limited area: Set the minimum area of the independent fine broken surface in the aggregation result, that is, the independent fine broken surface smaller than area will be eliminated. The area unit is consistent with the aggregation limit Distance unit. For example, if the unit listed above is selected as meter, the area unit here is square meter. The default is 0, which preserves all faces.
- Hole-limited area: Set the minimum area of the holes inside the aggregation result face, that is, the holes smaller than area will be filled. The area unit is consistent with the aggregation limit Distance unit. For example, if the unit listed above is selected as meter, the area unit here is square meter. The default is 0, which preserves the holes in all face features.
- Aggregation Field: Only elements with the same Aggregation Field value can be aggregated. For example, building surfaces should be aggregated. In principle, nearby water areas should not be aggregated. Supported field value types are: Boolean, Integer, Long, Date, Timestamp.
- Result Data: Set Result Datasource and Dataset Name.