Questions tagged [point-in-polygon]
A common GIS operation. Used to determine whether a point lies within a polygon's bounds.
344
questions
-1
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11 views
Checking points in polygons using Python [duplicate]
I have 2 dataframes, the first one contains 100 rows and the second one too. The first one contains buildings and their coordinates. The second one contains coordinates of parts of map and information ...
0
votes
0answers
27 views
Drawing a square manually using coordinates
I've load points coordinates from a .csv file on QGIS. These points are the intersection of a regular grid. I would like to select manually four point of this .csv file to draw a square polygon. Also,...
0
votes
1answer
27 views
Identify if the point lies inside the polygon in QGIS
I created a polygon using Iso-Area as polygons algorithm in QGIS. I have a point's coordinates and added it as a vector layer into QGIS. It is shown on the map that the point lies within the polygon. ...
0
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0answers
16 views
Checking if the point lies within the polygon in R using sf package
I have a point's coordinates as well as an object with the class of sfc_polygon in R. I would like to check if this point lies inside that polygon or not.
I created an object with the class of ...
3
votes
1answer
94 views
Counting points inside polygons by attribute using ArcMap
I am working with ArcMap 10.8 and extensions.
I have a grid (polygons) and another shapefile of points. I need to generate a field in the grid that shows me how many points are inside each cell, but ...
-2
votes
1answer
31 views
Seeking Python solution for point, line, and poly in poly intersections [closed]
I'm just learning Python, and I need a little direction. I've been reading many of the posts on this site, but I haven't found one that puts me on the right path. These operations are trivial in GIS ...
2
votes
1answer
140 views
Picking up the coordinates inside this polygon draw
I already have a geojson being consulted and that is plotting these black dots. And then I inserted the leaflet-geoman plugin to give users the freedom to create polygons on the map. Basically draw ...
0
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36 views
What strategies exist to speed up point-in-multiple-polygon searches? [duplicate]
Consider a scenario where you have polygons representing the border of every country in Europe. You also have the Lat/Long of a user's mobile device. You now want to display which country that user is ...
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35 views
Why is 'Count Points in Polygon' returning zero values for all NUMPOINTS?
I'm using QGIS and I have a file of points (Coyote_Clipped). I'm trying to count the number of points in each grid cell. I ran "Count Points in Polygon" on the grid and it worked without ...
3
votes
2answers
174 views
Counting Points in Polygon to analyze data using QGIS
I am using QGIS, and I have a shapefile that has 23 different land classifications. I have another file that lists coyote observations as points. I would like to find out how many coyote observations ...
4
votes
2answers
92 views
Polygon to Point Grid with the same information
I want a grid of points (with defined spaces between them) inside a Polygon. All the points should contain the same information as the original Polygon did.
I tried the centroid (only one point -> ...
0
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0answers
45 views
Why am I getting this error when using count points in polygon?
I'm using QGIS 3.16.1 and trying to work with the 'count points in polygon' feature. When I try to run it I get this error:
*QGIS version: 3.16.1-Hannover
QGIS code revision: b381a90dca
Qt version: 5....
0
votes
1answer
24 views
Create a table of points that intersect with polygons in ArcGIS Pro
I have a set of polygon and point data. Each polygon shares the same area with dozens of points. I want to create a table that shows which points intersect with which polygon. What is the best tool ...
1
vote
1answer
46 views
Calculating frequency of polygon types overlapping coordinate point
I have shapefiles of sea ice coverage for multiple days of the year. At each time-point (day) the sea ice is split into different polygons which corresponds to different ice types (i.e. fast ice, ...
4
votes
2answers
229 views
Combining CSV and shapefile to find area name where stations are located
I have one shapefile with marine areas. The other is a CSV file with some station names and coordinates. I would like to get table with stations names and corresponding marine area names, where the ...
0
votes
0answers
23 views
Generating random points with overlapping polygons in QGIS
The "Random points inside polygons" tool in QGIS works great to generate a fixed number or density of points within polygons; however, because QGIS does not link the polygon ID to the points,...
5
votes
1answer
150 views
Preventing labels from overlapping certain features using QGIS
I have two layers in my QGIS Project (QGIS 3.4.8). One in the foreground, which contains surfaces, and one in the background, which contains a point with labels, see image below:
The problem is that ...
4
votes
1answer
82 views
How to choose limited number of points to represent a point grid
I need to choose a few points to represent the grid below, e.g: 8 points in the grid below. This point need to be geographic distributed
This points needs to be geographic distributed. Lets see a bad ...
1
vote
2answers
50 views
Using QGIS to buffer attributes on map
This is my first experience of using GIS systems.
Firstly, to give you an overview of my project, I am trying to analyze the obesity rates within the boroughs of London. I have gotten to the point now ...
2
votes
1answer
97 views
Calculating minimum distance between two point layers within polygons in QGIS
I have three vector layers two points and one polygon:
Centroids (POINTS FROM)
NUTS_ID | CNTR_CODE | NUTS_NAME | id
Sorting_plants_2020 (POINTS TO)
postcode | name | where | capacity | id
...
3
votes
3answers
61 views
Calculating value of unique points in polygon in PostGIS
I'm working with a spatial PostgreSQL database that contains species records, there is a point layer 'spp_points', each point has a "spp_ID" and "spp_score" field. I also have a ...
2
votes
0answers
14 views
Generating equidistant Points inside box which also contains MultiPolygon [duplicate]
I have a box bounded by min_x, min_y, max_x, max_y, I also have a multipolygon = poly contained in that box. I'm trying to equidistantly scatter points throughout that box, outside of that ...
1
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0answers
35 views
Getting attribute form data from another layer
I’m trying to use the attributes form in QGIS 3. Most of what I’m doing is relatively simple use of combo boxes but I’ve run up against a wall.
The idea is that I’m trying to streamline how we notify ...
3
votes
1answer
84 views
Updating table from another table with function ST_CONTAINS in PostGIS
I tried to update an attribute 'solved' of a polygon table (table name: polygon) by using an attribute 'solved' of another point table (table name: point).
What I want to do is that if ALL the points ...
2
votes
1answer
79 views
Spatial joins in ArcMap (points to polygons) - capturing points that are just outside of outer boundaries
I am working with geocoded crime event data, and attempting to join that point layer with a census block group layer in order to get a count for each census block group (and ideally sums/averages for ...
2
votes
1answer
52 views
Automatically output joined fields in input layer while using spatial join
For example, I have two layers:
A polygon layer city block with a ID field city block index.
A point layer parking lot with a field parking lot size.
I want to know the total parking lot size for ...
0
votes
0answers
37 views
Returning all points within a polygon
I've been trying to figure out how to use ST_Contains to figure out what points are contained within a polygon.
Here is my query.
SELECT "userId", "firstName", "lastName",...
1
vote
0answers
44 views
Aggregating data and displaying counts with GeoPandas
I have two datasets that I want to use. The first is a shapefile of King County that has polygons broken up by school districts. It has boundaries saved as polygon features on a geo-dataframe.
The ...
1
vote
1answer
63 views
How to generate a column with a count of number of points in a polygon AND have 0 for the rows where there are no points in the polygon?
I have two data sets with a large number of points that I’m organizing into a hexbin grid.
I'm associating these points with the hexbin polygons by using PostGIS to determine if a point falls within a ...
1
vote
1answer
77 views
Count points within a polygon
I'm trying to count the number of points within a polygon of a fixed size in R. I'm planning to do it a few times so that I can eventually calculate average density of points with some measure of ...
1
vote
2answers
62 views
Spatial Join also Based on Attributes using QGIS
I have two data sets:
points with a timestamp
polygons representing neighbourhoods
I need to compute how many points are in each neighbourhood polygon, based on a time range. So in other words, how ...
0
votes
0answers
38 views
Dividing country into regions based on some initial center point using ArcMap
I am new to GIS.
I have some lat-long (say 5) spreads across a country and I want to make polygons around each point such that all the polygons cover the whole area of the country and within the ...
0
votes
0answers
37 views
st_intersection only if specific conditions are satisfied
I'm new to sf package.
I have two sf files, one containing lat/long position of points (point_sf) and the other one containing sf polygon geometries (polygon_sf). I want to see which points belong to ...
2
votes
2answers
63 views
Determining how many of my coordinates overlap with layer in QGIS
I am working on a project about a certain animal species. I have gotten coordinates from where the species has been observed.
Now I want to know what percentage of the observations are from gardens/...
2
votes
2answers
196 views
Counting points in polygons by weight and class in QGIS
I have seen a similar question to Counting points in polygon using weight and class simultaneously, but I was unable to operationalize the answer that I found so far.
I have a point layer with ...
2
votes
1answer
68 views
Counting points in polygon using weight and class simultaneously
I am using QGIS 3.1. I am wondering if there is a way to count points in polygons but by using both the weight and class.
For example, I have distributions of a number of species, each with a unique '...
3
votes
1answer
265 views
Fastest point-in-polygon solution with billions of points over thousands of polygons
Problem definition is quite simple: I need to achieve point-in-polygon detection for:
billions of lat/lon points
over thousands of polygons
I need to be able, for every point, to determine if it is ...
1
vote
0answers
66 views
Entry and exit point of the polygon
I would like to add to the attribute table somehow quickly a column containing the entry and exit kilometre data.
I have the available point layer with kilometre, road axis and polygon as shown:
...
6
votes
1answer
319 views
Count points in polygon grouping by attribute using PyQGIS
I have a point layer with an attribute table like this:
id_point class
1 A
2 B
3 A
4 C
5 B
...
What I need is to count how many points of ...
0
votes
0answers
36 views
Counting and print number of points from a CSV in a series polygons / buffered points in GEE?
I'd like to compare the number of calls from gps coordinates to the population around those coordinates in Google Earth Engine. My plan was to count the number of incidents (points from a table: ...
0
votes
1answer
41 views
Count points by non-continuous polygon in QGIS
I'm very new to QGIS and I'm learning by practice and reading both QGIS documentation and StackExchange answers. However, I think one of the main tasks has been naming the concepts correctly and look ...
2
votes
1answer
45 views
QGIS Random Points in Polygon PRESERVING Attribute Table?
I have a complicated shapefile of overlapping polygons. I need to generate random points inside each polygon, which is easily accomplished using Vector -> Research Tools -> Random Points Inside ...
0
votes
0answers
8 views
Calculating where map coordinates land within a collection of district boundaries? [duplicate]
The following coordinates make up the district boundaries of Westminster in the UK (point-to-point polygon):
51.4859, -0.1295
51.4846, -0.1498
51.4978, -0.1561
51.4978, -0.1796
51.5259, -0.2062
51....
1
vote
0answers
29 views
Fast solution to load and query shape files
I work on a .net core web API application collecting fishing events with latitudes and longitudes.
For each of these positions, I need to compute the corresponding Exclusive Economic Zone (EEZ), it's ...
0
votes
1answer
32 views
ArcMap: Identify mismatch between position of points from database with their actual location in polygons
A map in ArcMap contains two datasets:
Points J_i from table Jurisdiction of an SQL-database (SQL Server 2017) displayed by Display XY Data (Data Type: XY Event Source)
Polygon shapefile feature ...
2
votes
1answer
105 views
Points within Polygons given certain conditions
I am trying to locate all the points within a set of polygons given a certain condition on the polygon in MongoDB using Python 3x.
This question differs from the other ones because i) it requires ...
2
votes
1answer
31 views
Changing index order of points within the same polygon
I am currently trying to get rid of a waterway that divides my polygon. The problem is that the points are part of the same polygon but are around 190 rows away for each other.
Is there a way to ...
0
votes
0answers
28 views
OD matrix with origin and destination points based on polygons selections
I'm new in QGIS, and I would like to create an OD matrix. I have two shapefiles: one which contains the origins with POINTS(lat, long), and another one with destinations POINTS(lat, long). Each one of ...
2
votes
0answers
57 views
Optimising use of st_within for parallelisation
I'm trying to use st_within() to calculate points within polygons on a fairly complex shapefile. This operation tends to take 4-5 hours which is a bummer for debugging the code. I have access to a ...
0
votes
0answers
25 views
Calculate 70% of the area inside a polygon based on the polygon centroid
I am trying to generate an area within a polygon based on the polygons centroid that covers 70% of the containing polygons area. I generated the polygon centroids as points but I do not know how to ...
