A common GIS operation. Used to determine whether a point lies within a polygon's bounds.

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11
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2answers
65 views

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 ...
0
votes
1answer
37 views

constrain random points with a polygon in R using sp library

I have a map of London's waterways, which I've grided into a raster dataset to enable me to measure proximity to water from randomly generated points. What I'd like to do please is to constrain the ...
0
votes
0answers
16 views

Convert polygons to optimized lat long radius

I have a research project where I need to search Instagram and Twitter for geo coded data. The APIs allow lat, long, and radius, but I have shape files with polygon shapes and some long lines (think ...
2
votes
3answers
75 views

Counting points of specific type within polygon using ArcGIS ModelBuilder?

I'm analyzing wind farms and wind turbines within ArcGIS Desktop 10.2. My data consists of the locations of individual wind turbines that are associated with a wind farm (let's call it "Wind Farm ...
0
votes
0answers
13 views

Point data aggregation for choropleth

I have a sizeable amount of geotagged point data (>1M) and am looking to create a choropleth map of point data density based on boundaries I have in a shape file. I've added this to a fusion tables ...
0
votes
1answer
44 views

List all Points within Polygon using QGIS? [duplicate]

Complete newbie to QGIS and can't seem to find how to do this. I have created a map with 84 different polygons. Then I've imported approx. 8000 points. What I want to do is now query my map and get ...
0
votes
2answers
61 views

Points within polygon in QGIS [duplicate]

I have a shapefile with polygons. And I have a csv file with points. Now I want to know for each point in which polygon it is situated. Every polygon has a number, so I want to create a file where you ...
1
vote
0answers
31 views

Sample points based on underlying polygon attributes

I have a point shapefile and I would like to sample those points (just like the "Sample" tool allows points to sample underlying raster) to receive a table with underlying polygon values (interested ...
2
votes
0answers
45 views

QGIS's “Points in Polygon” counts zero in every census tract

I am mapping the location of incidents of asthma using QGIS. I would like to count how many points are in census tracts to better understand the areas where asthma occurs most frequently. My map ...
0
votes
0answers
88 views

Geofencing: Query if a POINT is within a POLYGON

I am trying to use the following query to search if a point is within a defined POLYGON (aka a geofence I want to define): ...
1
vote
1answer
27 views

Points in Polygon results in PNTCNT=NULL

I am trying to use the QGIS (2.6.1) vector analysis tool "Points in Polygon". The points originally came from a KML file and the polygons I created new. I initially had a warning about different CRS ...
0
votes
1answer
48 views

cross referencing files question

This may be an easy question so please forgive me if it is (or if it makes no sense) as this is all very new to me. I have 3 files that I am trying to cross reference. One file has columns category, ...
1
vote
0answers
76 views

Speed up row-wise point in polygon with Geopandas

I have a geopandas GeoDataframe which contains some attributes and a geometry column which is filled with shapely Point(lon, lat) objects. Moreover, there is a GeoSeries which is equally indexed as ...
2
votes
1answer
76 views

Why is Shapely and contains_point not detecting point being on land?

I'm using the world shape file that can be found at https://trac.openstreetmap.org/browser/applications/editors/merkaartor-branches/merkaartor-0.14-fixes/share/world_shp/world_adm0.shp?rev=17052. ...
1
vote
0answers
37 views

Arcpy script or other method for points in polygon per participant

Is there an Arcpy script or another way that I could use to find out the number of GPS points falling within each participant’s home neighbourhood as defined by an 800 meter network buffer around the ...
1
vote
2answers
200 views

Determine which points are contained inside a given polygon

I have these database tables defined: CREATE TABLE regions ( id SERIAL PRIMARY KEY, name VARCHAR(150) NOT NULL ) CREATE TABLE region_points ( id SERIAL PRIMARY KEY, region_id SERIAL ...
0
votes
2answers
155 views

Join spatial point data to polygons in R

I am trying to perform a spatial join between point data and polygon data. I have data that indicate the spatial coordinates of an event in my csv file A and have another file, shapefile B, that ...
0
votes
2answers
71 views

Mean values of points within a polygon layer

I have 2 shape files (1x points and 1x polygons). The points have different values (soil sampling results). What I want to do is to calculate the mean values of the points inside the different ...
2
votes
2answers
56 views

Why do I get green crossed circles instead when I try to move a point?

It's really horrible I must say. I sometimes have geometry issues and then try to go one by one through them and fix these cases. Therefore I mark the area points and delete them for instance. After ...
5
votes
3answers
1k views

How to identify feature vertices that are part of a donut hole in ArcGIS 10?

I´m exporting the coordinates of polygon vertices to a CSV-File using the "Feature Vertices to Points" and then the "Export feature attributes to ASCII" tools. Some of these polygons have holes ...
6
votes
2answers
5k views

Create a polygon layer from point data

I'm currently using QGIS 1.8.0 I would like to create a polygon layer from a point dataset, where the size of the polygons relates to the resolution of the grid reference. The ultimate aim would be ...
6
votes
4answers
2k views

Point in polygon algorithm for multiple polygons

I've a Google map with bunch of polygons on it. Here is a problem I'm interested in: Given a lat,lng point, what's the best way to determine all the polygons that this point lies in? The obvious way ...
2
votes
0answers
22 views

Aggregate nearby points to develop equally sized regions in QGIS

I have a list of 4,500 points (lat, long, unique id, attribute). I also have a service territory which all of the points fall into. I would like to break the service territory (polygon) into 6 ...
1
vote
2answers
618 views

Function for Selecting Points in a Polygon

I've been banging on this for a few hours, but since I'm relatively new to PostgreSQL and PostGIS, I can't find the solution. I'm trying to create a stored procedure (function) which will return all ...
2
votes
0answers
19 views

How to find out to which polygon each points belongs to in ArcMap [duplicate]

I have got a shapefile consisting of a number of polygons, and another shapefile with a number of points. I want to add a column in the points shapefile. For each point, I want the column to contain ...
3
votes
2answers
213 views

How to determine in which grid cell each coordinate of an x,y series is located?

I have a circular arena which I have divided into a number of equal-sized 'cells' using a grid-like arrangement of concentric circles and line segments (in grey below) and also a series of x,y ...
1
vote
1answer
60 views

Gdal+Geos point in polygon test fails under MinGW64

I have to build a grid of points and remove the points that falls inside a polygon. Polygons are defined in a ESRI shapefile, points are in a list. This is how I make the test: OGRLayer *layer = ...
0
votes
0answers
58 views

Generate random points in geometry near heatspots

I have an algorithm, that generates random points with in a given polygon (Generate random points in polygon. Algorithm question). The Polygons the points are generated in are communities or districts ...
1
vote
2answers
323 views

How to implement a spatial query on polygon data for a specific point?

I have vector data fed into a database which returns a report at province level upon querying. This is implemented in a web tool. I want to add an extra functionality at point level, where I can ...
0
votes
0answers
101 views

How to generally determine if a Point is inside a Polygon/Region?

I have a region (i.e. closed polygon) like this given in cartesian coordiantes: 1: 628497 / 239586 2: 642383 / 249881 3: 657705 / 241262 4: 652677 / 230489 5: 631370 / 231446 6: 628497 / 239586 I ...
0
votes
1answer
97 views

Point-in-polygon using WGS84 geographic coordinate system

When running a point-in-polygon operation, is it valid to run that with polygon features in straight up WGS84 and a point in lat/lng, or should both be projected into a non degree based coordinate ...
0
votes
0answers
33 views

Capturing points slightly out at sea

I have two tables one containing points (points) and the other polygons (polygons). I want to generate a two-columns table identifying for each point of the first table the polygon containing it. So ...
1
vote
3answers
124 views

How to Count point in polygon + on boundary?

So I'm looking for suggestions in both ArcGIS 10.2 and QGIS on methods on how to count points within a polygon and points that fall on a polygon boundary without adjusting the data/points. The ...
1
vote
1answer
37 views

Point in zone problem in calculation

I have a strange problem that i believe its because the zone pass through international date line. My goal is to find if a point is within a zone and I use the geoPHP library, everything seems to be ...
7
votes
3answers
2k views

Overlay a spatial polygon with a grid and check in which grid element specific coordinates are located

How can one use R to split a shape file in 200 meter squares/sub-polygons, plot this grid (incl. ID numbers for each square) over the original map below, and evaluate in which square specific ...
2
votes
0answers
48 views

Match housenumbers on buildings (special case of point-in-polygon-test)

Task with example I'm working with geodata (country-size) from openstreetmap. Buildings are often polygons without housenumbers and a single point with the housenumber is placed within the polygon of ...
2
votes
2answers
90 views

Finding a point inside a polygon based on maximum value of a specific field

I have a Polygon Shapefile that represents US counties and a Point Shapefile that represents hospitals. The hospital attributes table includes fields like "Number of Beds", "Number of Patients" and ...
2
votes
0answers
98 views

QGIS assign multiple points data to closest polygon

I've got two layers: point layer polygon layer I need to add the points attributes to the polygon by location (if the point is on top of polygon add the atribute as a new field. I thought of ...
-1
votes
2answers
167 views

Postgis: Point-in-polygon check + feature attributes inheritance

I have two tables in Postgis 2.1 database: Polygon features with a reach attributive information; Regular point grid; I would like to get a SQL query returning the regular point grid with ...
2
votes
1answer
302 views

Find all street names or addresses within a polygon

I have a geojson list of lat/long coordinates that make up a custom polygon of a section of my county. Ideally I would like to be able to find all the addresses that are within the polygon boundaries. ...
2
votes
1answer
71 views

Positons from GPS lanes inside a polygon

i have a lot of lanes like the orange lanes at the below picture (latitude and longitude values). Now i need all values from each lane inside the red polygon. What is the easiest way to realize ...
3
votes
2answers
2k views

Count Points in Polygon with Postgis

I've got a simple problem: I want to count the number of points within a set of polygons. I have a SQL already but it only gives back the gid of the polygone that actually contains points. My ...
2
votes
2answers
596 views

Select points within a polygon and update attributes

This seems really simple but I can't get it to work. I have two feature classes, a polygon of sales areas for a city, and point layer of addresses. I want to select the addresses based on the sales ...
1
vote
0answers
51 views

Using Geoserver

I am new to GIS and interested in using Geoserver. I have had a look at tutorials and read some books on this but still feeling clueless. I intend to use C# to accomplish some tasks eg, plot points on ...
6
votes
3answers
6k views

Check if lat/long point is within a set of polygons using google maps

I know how to do the above using Esri (Query task on shapefile), but can this also be done using Google Maps? Do I have to query each polygon or is there one method to query a set of polygons?
1
vote
0answers
107 views

node.js GeoLib fails on polygon that straddles the anti-meridian

geolib.isPointInside does not appear to work correctly when the polygon longitudes straddle the anti-meridian. I maintain a system with lots of polygons that do straddle the antimeridian (I'm in ...
2
votes
1answer
56 views

How to get only one biggest point in polygon?

I have polygon and point feature classes. Every polygon have 2 points inside them. For output I need only one point with highest value. I need incorporate this step in ModelBuilder. I had idea about ...
1
vote
1answer
97 views

Associating location data from PostGIS for a Choropleth map?

I'm trying to build my first choropleth map from data that we have stored in our PostGIS enabled Postgres database. So far I've been able to build a map on Mapbox using a topojson set of UK postal ...
1
vote
1answer
652 views

Geodjango - trying to get points within a polygon

I'm going through the Geodjango tutorial and trying to implement in my own project - I have loaded data from a shapefile into my model/database and I have a separate model that has a PointField. I am ...
1
vote
1answer
138 views

Closest point on a line segment from point outside the line

From the above pic I found the value x from line (p1,p2) and point a. Using y=mx+b and an imaginary red line which is perpendicular to the black line having slope -1/m and the intersecting point ...