Questions tagged [de-9im]
The Dimensionally Extended nine-Intersection Model (DE-9IM) is a topological model and a standard used to describe the spatial relations of two spatial objects.
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Why the * and not an F at position (2,1) in the intersection pattern matrix of the Contains predicate
The Contains intersection pattern matrix should be: T*****FF* according to [1], [2] and [3] (but strangely not [4]... for which the matrix is symmetrical, hence Contains==Within, which is not correct ...
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PostGIS function to get the corresponding intersection matrix pattern for any of the 8 spatial relationships between two geometries
I have a quick and very simple question for which I have not (yet) been able to find an answer:
is there a PostGIS function to get the intersection matrix pattern corresponding to any of the 8 ...
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What is the pattern matrix equivalent of ST_Equals()?
Within the OGC Simple Feature Access Part 1, I found this:
Whereas, in PostGIS (3.4.0dev 3.3.0rc2-335-gae95dd219):
SELECT ST_RelateMatch(
ST_Relate(
'LINESTRING(1 1, 2 2)',
...
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What exactly are the definitions of the boundary and interior of a line or a point?
Regarding the DE-9IM and the OGC spatial predicates for expressing relationships between two geometries; I'm wondering what exactly are the boundary and interior of respectively a line and a point? Is ...
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Is the boundary of a polygon comprised in its interior?
I'm wondering, regarding the DE-9IM and the OGC spatial predicates for expressing relationships between two geometries; is the boundary of a polygon comprised in its interior or not? If not, does it ...
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Role of boundaries when using shapely within function
According to the shapely documentation:
object.within(other)
Returns True if the object’s boundary and interior intersect only with the
interior of the other (not its boundary or exterior)
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ST_RELATE - Intersect ignore shared boundary
Using postgis I am trying to find polygons that intersect, ignoring polygons that only have a shared boundary (edge).
ST_Relate(g1, g2, 'T********') is a standard intersection.
ST_Relate(g1, g2, 'TF*...
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postgis st_relate polygon inside another and sharing a boundary
I am trying to select polygons inside an other one WITH a common boundary.
It seems that st_relate is the way but I can't find the right matrix, even if I don't see where the fault is in :
st_relate(e....
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How to determine if a Polygon is inside another Polygon's hole
Given two valid polygons P and Q, what's the cheapest / fastest way to determine:
If polygon Q is inside one of polygon P's holes (interior rings), or vice versa. (see illustration below)
To the ...
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Boundary of MultiLinestring in DE-9IM
can somebody help me understand (probably giving visual examples) what does this sentence mean which is quoted from the wiki page of nine intersection model:
Those points that are in the boundaries ...
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Using DE-9IM patterns in python plugin for QGIS?
I'd like to compare geometries using DE-9IM patterns in my QGIS plugin written in Python. I've tried to instantiate QgsGeos but it seems there's no such module in qgis.core, as reported by the ...
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What is the difference between Spatial predicates "Covers" and "Contains"?
I try to understand the Spatial predicates of the DE-9IM Intersection matrix. I don't get the difference between predicates Covers (respective CoveredBy) and Contains (resp. Within).
I try to draw ...
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How does spatial polygon %over% polygon work to when aggregating values in r?
I'm working on an environmental epidemiology project where I have point exposures (~ 2,000 industrial hog operations - IHOs). These IHOs spray on nearby fields, but the feces water droplets and smell ...
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Regarding spatial relationships, what is the Dimensionally Extended 9 Intersection Model (DE-9IM)? [duplicate]
In plain English what is the Dimensionally Extended nine-Intersection Model (DE-9IM)?
What is the meaning of each row/column in the matrix?
How can I use that information to build a relation matrix?...
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Get DE-9IM matrix in spatialite?
Is there a way to get the DE-9IM matrix between two geometries in a Spatialite function, analogous to the st_relate() function in PostGIS?
(I find it very helpful to spatially join using intersect() ...
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What topologic relation means "interior-disjoint"?
I am using the JTS Topology Suite, and trying to write an expression that means "shape A and shape B are interior disjoint".
I read this documentation page but I don't entirely understand the ...
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SQL Server STRelate equivalent of Oracles SDO_RELATE(...mask=anyinteract)
In Oracle Spatial, we are running checks on a graph. The Check should provide Nodes, which are marked as endnodes (Attribute "EDGEDEGREE" equals 1) but are in fact located somewhere along an edge. We ...
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How do I describe a special relationship between connected edges?
Consider this simple situation where three edges connect at a node:
I’d like to write a succinct and clear description of the relationship between A and B in such a way that differentiates it from ...
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Is there a standard st_relation_readable() function for translate DE-9IM strings?
Spatial databases, such as PostGIS, implement the DE-9IM model with function st_relate(),
which returns a string with domain of {0,1,2,F}, meaning 0=point, 1=line, 2=area, and F="empty set"...
See DE-...
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