Search direct neighbors.
The operator ::find_neighbors determines neighboring regions with Regions1 and Regions2 containing the regions to be examined. Regions1 can have three different states:
- Regions1 is empty:
In this case all regions in Regions2
are permutatively checked for neighborhood.
- Regions1 consists of one region:
The regions of Regions1 are compared to all regions
in Regions2.
- Regions1 consists of the same number of regions as
Regions2:
In this case all regions in the n-th position in
Regions1 and Regions2 are checked
for a neighboring relation.
The operator ::find_neighbors uses the city block distance
between neighboring regions. It can be specified by the
parameter MaxDistance.
neighboring regions are located at the n-th position in
RegionIndex1 and RegionIndex2, i.e.
the region with index RegionIndex1[n] from Regions1 is
the neighbor of the region with index RegionIndex2[n] from
Regions2.
Covered regions are not found!
|
Regions1 (input_object) |
region(-array) -> Hobject: HRegion(Array) |
| Starting regions. | |
|
Regions2 (input_object) |
region(-array) -> Hobject: HRegion(Array) |
| Comparative regions. | |
|
MaxDistance (input_control) |
integer -> HTuple.long |
| Maximal distance of regions. | |
| Default value: 1 | |
| Suggested values: 1, 2, 3, 4, 5, 6, 7, 8, 10, 15, 20, 50 | |
| Typical range of values: 1 <= MaxDistance <= 255 | |
| Minimum increment: 1 | |
|
Recommended increment: 1 | |
|
RegionIndex1 (output_control) |
integer-array -> HTuple.long * |
| Indices of the found regions from Regions1. | |
|
RegionIndex2 (output_control) |
integer-array -> HTuple.long * |
| Indices of the found regions from Regions2. | |
The operator ::find_neighbors returns the value H_MSG_TRUE if the input is not empty. The behavior in case of empty input (no input regions available) is set via the operator ::set_system('no_object_result',<Result>). The behavior in case of empty region (the region is the empty set) is set via ::set_system('empty_region_result',<Result>). If necessary an exception handling is raised.
::threshold, ::regiongrowing, ::connection
::spatial_relation, ::select_region_spatial, ::expand_region, ::interjacent, ::boundary
Region processing
