Questions tagged [multi-polygon]
The multi-polygon tag has no usage guidance.
54
questions
0
votes
1answer
23 views
How to get union of multiple polygons in Google Earth Engine?
I would like to get the union of m (m is variable) different (multi)polygons in Google Earth Engine. The attribute .union() only works with two polygons. See example below for what I have till now.
...
0
votes
1answer
71 views
PostGIS: Split polygons into intersecting and non-intersecting and grouping on overlap
I have a big query that I am looking to optimize. I am matching millions (expanding daily) of rows with Points against a mostly read-only table of (tens of thousands of) areas with (Multi)Polygons. ...
2
votes
0answers
43 views
Selecting polygons within other polygons in the same layer in QGIS
I am trying to filter out certain infrastructure from OSM data and convert everything to simple point layers using QGIS.
I have an OSM shapefile containing polygons of schools. In many instances, ...
2
votes
1answer
62 views
Cleaning up holes in MultiPolygon using QGIS
This is a screencap of my map in QGIS:
Those orange bits in the middle of each section are actually holes in the GeoJSON file and I can't make them go away. I've tried using the "Vertex tool&...
2
votes
2answers
66 views
Turn a MultiPolygon with Nested Shells into a Polygon with Holes
I am reading GeoJSON into shapely objects and need help,
I have a massive MultiPolygon with several nested Polygons in it. I believe this is why it is not considered a valid shape?
as_shape.is_valid
-&...
2
votes
1answer
74 views
Getting the bigger polygon of Multipolygon
I have a Multipolygon that has 5 separate polygons and I want to get only the geometry of the biggest polygon.
How can I get the largest polygon from the multipolygon?
3
votes
2answers
79 views
Buffering around all borders of EEZ regions in QGIS
I have a layer containing points (in yellow) and a layer containing the Exclusive economic zones of all countries (as polygons, its geometry is MultiPolygon). See the image below:
I would like to ...
0
votes
1answer
54 views
Calculating/obtaining a "centerpoint" inside a multipolygon entity with FME software?
Obviously, this point does not necessarily have to be the real centroid, but it does have to be a, only one, single interior point of each multipolygon.
What I have found is the CenterPointReplacer ...
3
votes
0answers
73 views
Error using PostGIS query in MultipolygonZ type data [duplicate]
I am using this query in MultipolygonZ type data in my PostgreSQL database, but I got error for so many times the data is not rendered properly in PostgreSQL with PostGIS extension.
PostGIS query:-
...
0
votes
1answer
19 views
Partial perimeter in ArcGIS
I have a set of polygons, in turn formed by several polygons. Let's suppose a large polygon formed by three smaller polygons.
Is there any method to know the outer perimeter of the set of three ...
2
votes
1answer
156 views
Splitting MultiPolygon shapefile into separate Polygons in R
I have a polygon shapefile with 2 features. I want to split the MultiPolygon shp into separate shapefiles based on a column of the attribute table. What I've tried so far is this code based on that ...
3
votes
1answer
82 views
QGIS to inspect individual polygons of multipolygon
Using QGIS's Identify results, I can highlight and inspect an individual 'feature', in this case a country geometry. In reality, the geometry is a Multipolygon and I would like to inspect individual ...
0
votes
0answers
33 views
Opening one corresponding related table in attribute form for selected feature in multipolygon in QGIS
I have MultiPolygon A with 9 features, each feature should be described by one non-spatial attribute table with 10 - 500 features. I tried to create 9 relations like A-to-Table1, A-to_Table2 ...A-to-...
4
votes
1answer
332 views
Converting from MultiPolygon to Polygon in PostGIS
I have a table in PostGIS, where the data is currently stored as a MultiPolygon. Each Multipolygon has only a single Polygon in it.
How do I query and get the containing Polygon, and not MultiPolygon? ...
4
votes
3answers
723 views
R/sf: Some edges are crossing in a MULTIPOLYGON. How to make it valid when using S2 geometry?
Goal: I would like to know the NUTS region (2016 version) of points in Europe.
Method: (1) Download the official geodata from Eurostat, (2) Use st_join from sf with R.
Problem: I've updated sf, now ...
1
vote
0answers
42 views
Merging MultiPolygon and MultiLinestring
I want to merge a Multipolygon with a MultiLinestring however I cannot merge the data as they are of different types.
One solution was to create a minimal buffer around the MultiLinestring and merge ...
0
votes
0answers
49 views
Multiple 3D polygons to a single 2D MultiPolygon having individual overlapping features or a single 3D MultiPolygonZ
I narrowed a 3D problem to a GeoDataFrame G containing four Shapely polygons, each is a 3D flat triangle. In 3 dimensions, these polygons all share a common summit and also a common edge, 2-by-2. They ...
1
vote
0answers
79 views
How to convert a multipolygon to multiple single polygons
I have a polygon clipping function in my OpenLayers app which may return me a multipolygon.
Unfortunately, my app does not support multipolygons by design. So I need to convert a multipolygon to ...
1
vote
0answers
68 views
QGIS Difference Algorithm: multilinestring won't work with multipolygon layer
I am working with two vector layers in QGIS (location: Indonesia). I want to 'subtract' the area of layer 1 ('Forest_buffer') of layer 2 (Scenario_1). I am using the Difference algorithm. Layer 2 is ...
1
vote
0answers
101 views
Extend the contours of the polygon into a polygon
I would like to be able to extend the vertices of one polygon to the edge of another polygon, how does the snapping between poligons using python.
The photo shows a representation of my problem.
I ...
0
votes
0answers
33 views
Optimizing minimum distance calculations between multiple polygons in R
I have a list of polygons and would like to create a minimum distance matrix by calculating the minimum distance between each possible pair. I am currently using the code below, but this is running ...
1
vote
0answers
38 views
Getting error while trying to read multipolygon data using shapely wkt.loads (Python)
I have a CSV file from which I'm trying to read multipolygons using wkt.loads of shapely.
While this works:
from shapely import wkt
x='MULTIPOLYGON(((18.62981086588664 73.79447461830097,18....
0
votes
0answers
33 views
Getting centroid of multipart polygon using ArcPy
I am trying to get the center of a multipolygon, I have tried doing:
with arcpy.da.SearchCursor(fc, ['SHAPE@']) as cursor:
for row in cursor:
multipoly = row[0]
centroid = ...
0
votes
1answer
28 views
Matching polygons to intersecting polygons using ArcMap
I am trying to match a set of polygons (A) to another set of polygons (B) using ArcMap. Both sets overlap themselves, and each other. Here's an example of what it looks like in my data:
The green ...
2
votes
0answers
31 views
Separate multipolygons into equal parts
I am trying to separate a multipolygon into equal parts. I am aware of the divide polygon plugin and that worked well for me in previous examples where a single polygon is involved. Unfortunately I ...
0
votes
1answer
312 views
How to convert Multipolygon to GeometryCollection?
I get this error (Script Error, File too large: larger than 512kb) in Google Earth Engine and my layer is a Multypolygon, just with 86 polygons. I have another layer with 300 polygons without any ...
0
votes
1answer
34 views
How to flatten a PolygonZ onto the XY-plane using pygis
I want to flatten/project a PolygonZ onto the XY-plane. Although I wished for a method to flatten the whole object with the option of letting me decide what direction of the the line needs to be ...
1
vote
1answer
82 views
Rendering overlapping polygons without holes in multipolygon in Leaflet
Is there a way to render overlapping polygons without holes in multipolygon in Leaflet?
I found Leaflet has an open issue.
codesandbox.io
I am asking because I have a bound polygon that contains inner ...
1
vote
0answers
38 views
Geometry converts from Polygon to Multipolygon in PostGIS
I'm having difficulties with the Geometry types in PostGIS and/or ArcPy and hope some of you can shed a light on what I'm missing or how I can fix it.
I have a .gdb containing Polygons. The Table in ...
0
votes
1answer
40 views
Using symbology for representing start and end (polygon / point) in QGIS
I have records with two geometry columns per record. I have been looking at different options to show them in QGIS:
Create two layers (one for start and one for end)
Create a multipolygon that merges ...
4
votes
1answer
83 views
Creating polygons with "Create shapefile layer" always produce multipolygons instead of polygons when saving in QGIS
Not sure if is a bug or I'm missing something.
Every time i'm creating a new shapefile with "Create shapefile layer" i got a multipolygon instead of a polygon (at least is what I'm expecting)...
3
votes
1answer
130 views
Error when calculating final polygon after subtracting all intersecting polygons using shapely
This question is a follow-on question from Calculating final polygon after subtracting all intersecting polygons using shapely which was answered.
I have a list of centroids that I buffer to 5000 ...
6
votes
4answers
509 views
Taking only the largest polygon from multi-polygon layer in QGIS
I have multi-polygon geometries in my file, and I want to take only the largest polygon within the multi-polygon geometry to further work with it. I tried using Geometry Tool Multipart to Single part, ...
1
vote
1answer
98 views
Getting a count of points in a multipolygon?
I have a set of lottery retail locations, latitude and longitude, that I transformed to points and added the geometry column like this:
ALTER TABLE lottery.retailers ADD COLUMN geom geometry(Point, ...
6
votes
3answers
378 views
Multipolygon supposed to be contained by another but returned False with Shapely
There are two multi-polygons a and A where a is supposed to be contained inside A. Using shapely, the following difference operator
b = a.difference(A)
print(b)
gives
POLYGON EMPTY
However testing A....
0
votes
1answer
634 views
Change geometry type to Polygon and MultiPolygon in PostGIS
I try to insert geometry values into a column in PostGIS. However, the type of values is a mix of MultiPolygon and Polygon.
I tried to change the column type to Multipolygon with:
Alter table ...
2
votes
2answers
432 views
Create MultiPolygon from Dataframe column
I have a dataframe with a column called geo_shape, for each row in this column data is in the format str with the following structure:
{"type":"MultiPolygon","coordinates"...
1
vote
2answers
187 views
PostGIS: Syntax for ST_Collect into a multipolygon keeping internal boundries
I have a PostGIS table with many polygons representing islands these all form a common group
How do I create a new MultiPolygon (keeping internal boundaries) and give it a new name?
CREATE TABLE ...
1
vote
0answers
71 views
Converting multicolumns CSV to Raster Format
I need to convert multicolumn CSV file in a raster.
I read some similar question, but my problem is that I have different columns in addition to "longitude" and "latitude" (I would ...
2
votes
0answers
97 views
Simplifying parts of polygons in QGIS
Is it possible to simplify just the selected parts of a polygon? I am trying to make a simplified version of the Australian Local Government Areas (LGAs) shapefile.
I am using the v.generalise ...
0
votes
1answer
87 views
Geoserver Vector tiles hollow issue with layer
I am using vector tiles from PostGIS, Geoserver for the world layer,
I have multiple layers for the global level,
I have seen multiple holes and missing tiles of some boundaries in the layer of vector ...
7
votes
1answer
2k views
Creating centroid inside of polygon [closed]
I want to get the centroids of my multipolygons using Python and GeoPandas. But when viewing the polygons and the centroids points on QGIS, the centroids are not inside the polygons.
Here is the code ...
0
votes
0answers
30 views
Simple way to convert GeoJSON from MultiPolygon into Polygon [duplicate]
I need a GeoJSON file that simply has the coordinates of the polygons for the boundaries of the provinces of Canada.
I have a GeoJSON file but it has multipolygons and my software does not support ...
0
votes
1answer
651 views
ST_GEOGFROMTEXT Multipolygons converted to Polygons BigQuery
My table contains multipolygons in column called BoundaryWKT, which is in a string format. I used function ST_GEOGFROMTEXT(BoundaryWKT) to convert column of multipolygons from string format to a ...
2
votes
2answers
163 views
Export/convert Points to Polygon
I have to convert a .shp into a .csv file and upload it to the SQL Server, for a program that only supports Polygon format and can not render Points.
Is there a way to convert Points to Polygon or is ...
1
vote
1answer
39 views
Extracting categorial data from neighboring polygons from st_intersects [closed]
For each polygon in an sf object, I need to extract data on a single variable from all of the neighboring polygons. I have made a reprex below.
So far I have managed to get a list of the neighboring ...
2
votes
1answer
226 views
ogr2ogr Conversion Clockwise to Counterclockwise?
Looking for the right combination of ogr2ogr parameters to get a .shp bundle to GeoJSON and reverse the Coordinate pairs. I recognize that ESRI defines Polygons as clockwise (http://www.esri.com/...
1
vote
2answers
229 views
PostGIS: create new polygons in between existing?
PostgreSQL: I have a PostGIS multipolygon table containing millions of features. It covers 95% of the country, however there are gaps between individual polygons. How can I fill these gaps with new ...
0
votes
1answer
173 views
How can I create multipolygon using shapely?
I am going to create polygon, but it produce invalid polygon form this data:
[[ 0 438]
[ 0 428]
[ 0 427]
[ 6 428]
[ 9 434]
[ 11 439]
[ 7 443]
[ 3 446]
[ 0 448]
[ 0 452]
[ 0 452]
[ ...
1
vote
1answer
34 views
Using multipolygon shape layers in profile tool
I am working with QGIS for some time. The profile tool is indeed very useful to visualize the 3D problems. My problem now is associated with this tool.
I have a multi polygon shape layer which I ...
