union2union2Union2Union2union2 (Operator)
Name
union2union2Union2Union2union2 — Return the union of two regions.
Signature
Description
union2union2Union2Union2Union2union2 computes the union of the region in
Region1Region1Region1Region1region1region_1 with all regions in Region2Region2Region2Region2region2region_2.
Internally, all regions of Region2Region2Region2Region2region2region_2 are united to
a single region before the individual regions of
Region1Region1Region1Region1region1region_1 are united with the already united region. This
means that union2union2Union2Union2Union2union2 is not commutative!
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Processed without parallelization.
Parameters
Region1Region1Region1Region1region1region_1 (input_object) region(-array) → objectHRegionHObjectHRegionHobject
Region for which the union with all regions in Region2
is to be computed.
Region2Region2Region2Region2region2region_2 (input_object) region(-array) → objectHRegionHObjectHRegionHobject
Regions which should be added to Region1.
RegionUnionRegionUnionRegionUnionRegionUnionregionUnionregion_union (output_object) region(-array) → objectHRegionHObjectHRegionHobject *
Resulting regions.
Number of elements: RegionUnion == Region1
Complexity
Let F be the sum of all areas of the input regions. Then the
runtime complexity is O(log(sqrt(F)) * sqrt(F)).
Result
union2union2Union2Union2Union2union2 always returns 2 (H_MSG_TRUE). The behavior in case of
empty input (no regions given) can be set via
set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>)
and the behavior in case of an empty input region via
set_system('empty_region_result',<Result>)set_system("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)set_system("empty_region_result",<Result>).
If necessary, an exception is raised.
Possible Predecessors
thresholdthresholdThresholdThresholdThresholdthreshold,
connectionconnectionConnectionConnectionConnectionconnection,
regiongrowingregiongrowingRegiongrowingRegiongrowingRegiongrowingregiongrowing,
pouringpouringPouringPouringPouringpouring
Possible Successors
select_shapeselect_shapeSelectShapeSelectShapeSelectShapeselect_shape,
disp_regiondisp_regionDispRegionDispRegionDispRegiondisp_region
Alternatives
union1union1Union1Union1Union1union1
See also
intersectionintersectionIntersectionIntersectionIntersectionintersection,
complementcomplementComplementComplementComplementcomplement
Module
Foundation