Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [polygon]

On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique.

3
votes
2answers
157 views

Creating polygon from hole in QGIS?

I work with this polygon and try to find a way to create a new polygon from the empty gap in the middle of the polygon. I succeed to do it with a "difference" tool- but used with another layer on the ...
0
votes
1answer
15 views

How to free the memory of return value of OGRGeometry::Buffer()?

I have in C++ (gdal 2.3.2) OGRPolygon poly; OGRGeometry* geom = poly.Buffer(1e-12, 1); now how do I free the memory allocated for geom after done using it?
0
votes
1answer
43 views

Using centroid point to generate polygon using ArcPy? [on hold]

Is this possible to generate polygons from points (which are centroids of future polygon)? I got shapefile with ~250 points + they have got two attributes: length and width. I don't need complete ...
1
vote
1answer
35 views

Two adjoining lines becomes clearer than two individual

When having an outline style where the two edges interfere, they become much more dense in the color than when they are individual, see image below. It is an outline of a polygon. The thing is that ...
2
votes
1answer
40 views

Expanding Polygon by distance using PostGIS?

I am trying to expand a polygon in a particular manner with PostGIS. I need a new geometry that is a bit like a Buffer, except Buffer produces rounded corners (lots of vertices) when using it on a ...
0
votes
1answer
58 views

Lines in Polygon Analysis

This question is similar to the "points in polygon" analysis, but I want to keep the attribute data for multiple lines within a single polygon. The data source is multiple line segments representing ...
0
votes
0answers
10 views

R Clip Simple Features Multiple Polygons with a Polygon (or another multi-polygon)

I have two polygon layers, a set of aquifer polygons and a set of district boundaries. I'm trying to clip the aquifer layers to be in only the districts that I want. From examining the other posts ...
2
votes
1answer
28 views

Distance from edge of each polygon to nearest point, such that points within each polygon aren't included

Using ArcGIS 10.5, I have a cluster of polygons that represent districts (together this cluster of polygons creates a nation). I also have thousands of points that represent offices. I would like to ...
2
votes
1answer
39 views

Cleaning topology errors in PostgreSQL (vector data) using QGIS?

I need to append the shapefiles to a PostgreSQL database. Once the data gets appended to PostgreSQL, some topology errors like gaps & overlaps can be seen. By using the v.clean tools the topology ...
2
votes
0answers
25 views

Graduated color display of overlapping polygons in ArcMap

Is there a way to display overlapping polygons in a graduated color symbology based on the level of overlap within the same feature layer? For example, in one area of the map there are two polygons ...
0
votes
0answers
32 views

Erroneous contour polygons in QGIS 3

I have a global DEM and try to calculate contour polygons for 4 different heights in QGIS. In the first image below, you can see the colored DEM (white = lowest; yellow = higher; orange = highest) as ...
0
votes
0answers
28 views

Edge matching polygons

I am trying to match the edges of two polygon layers. One is Orleans county, NY and the other layers is Monroe county, NY. Since the Orleans county is from a different source, the boundaries are not ...
1
vote
1answer
42 views

Export MultiPolygon data as WKT from QGIS 3

I have the polygon data for the city of Kamloops in QGIS 3. When I try to copy features of this polygon and try to paste it over here: https://arthur-e.github.io/Wicket/sandbox-gmaps3.html I don't get ...
0
votes
0answers
9 views

PAEK smoothing tolerance

How should one determine what the Polynomial Approximation with Exponential Kernel smoothing tolerance should be when smoothing a shape file using the Smooth polygon tool
2
votes
0answers
15 views

Removing a 'non-gap' gap from a polygon that straddles +/- 180 longitude; looking for an R-based, code solution

I am working with a set of polygons from here: http://lme.edc.uri.edu/index.php/digital-data. In the artic, there are several polygons that straddle the +/- 180 longitude line. These are single ...
2
votes
2answers
75 views

Cannot select polygon from shapefile in QGIS?

I am working currently on a small-scale map using among other sources Natural Earth shapefiles (NE). For an unknown reason, one of the polygons created by me on the basis of the fragments of NE ...
0
votes
1answer
50 views

Vectorizing black and white PNG? [closed]

I have a PNG map with just black and white colors, where black is the one pixel border. I want this in vector, or want an easy way to draw 90 degree polygons. I tried some things from forums but I ...
1
vote
1answer
33 views

Converting SHP UTM to decimal lat/long

I am trying to compare a list of lat/long to a shapefile and see which points are in or out of the polygon. I have discovered my shapefile is seemingly giving points in a UTM format. Below are some of ...
1
vote
1answer
31 views

Automating point feature class placement inside polygons using specific parameters?

I am trying to generate a point feature class of possible plot centers for a research project. The plot centers will be inside of defined forest stand polygons which are aggregated in various ways ...
0
votes
0answers
23 views

How to write multiple polygon Lat Lon info into a shapefile?

I have the Lat Lon information of the boundaries of 43 shapefiles. Now I want to combine all these 43 polygons into a single shapefile. How can I do that? What I did is I converted every polygon to a ...
0
votes
1answer
24 views

Remove rectangles from Leaflet map

I am drawing a Leaflet map. I also want the ability to add the coordinates via a form. How is that done? leaflet map
0
votes
1answer
18 views

Fill the color of polygons with some attribute value using ArcGIS

I have a large set of polygon features where I need to add some attribute value in "Name" field. Because it is a large set of polygons I want to have all polygons where I have add the value to be ...
0
votes
0answers
8 views

Drawing polygon and summarizing values in map on Portal for ArcGIS?

I have a map application created in Portal for ArcGIS. I have a points layer in the map. Each point has a numeric value. I want to be able to draw a polygon on the map, containing some of the points. ...
0
votes
0answers
43 views

Agricultural land swapping using QGIS? [duplicate]

I work for a company that owns agricultural land. Our new project is consolidating the small plots we own by swapping with other owners. We have a village were we managed to find all big owners and to ...
0
votes
0answers
19 views

Initiating infowindow event by clicking within KML polygon?

I generate multiple google maps kml polygon overlays in response to users query and can get the infowindow to launch by clicking on the boundary of the polygon, but can't seem to figure it out how to ...
1
vote
1answer
11 views

Keep only one geometry type when clipping polygons to sqlite with ogr2ogr

I have a regular grid of polygons and want to clip them using ogr2ogr. While using sqlite files as destination I stumbled over some wierd behavior: When clipping polygons exactly at their borders, a ...
0
votes
1answer
90 views

Plot times series for stack raster based on a polygons in my area

I am using R language and I would like to create a EVI MODIS time series plot, EVI vs time. I can did method to create a raster stack and plot the average EVI of the total area over time. But I ...
3
votes
2answers
100 views

Simplify polygon QGIS [duplicate]

I have a layer of polygons that are pretty detailed. I need these to be more simple. Is there a way to make this into a polygon with just the outer boundries?
2
votes
1answer
40 views

How to find intersection polygons in single layer on QGIS version 3.4.2?

I have polygons intersection in single layer. I want polygon in yellow frame and use polygon intersection to calculate area , how to do this?
0
votes
1answer
20 views

Extract a list areas and indices of multi-part polygons (SpatialPolygonsDataframe) R

I'd like to extract a list of polygons from a SpatialPolygonsDataFrame that include more than one area (so a polygon with a hole for example, or just 2 areas in one polygon entry in general). There ...
1
vote
2answers
35 views

Getting features for one polygon into another, Geometries do not line up using ArcGIS Desktop?

I have: - Census Blocks - Taxi Zones The taxi zone shares a rough boundary with census blocks, but there are times where there is overlap due to a rough outline(In image, red line is Taxi Zone, ...
-1
votes
0answers
20 views

What data formats do I need to use for polygons and points if I want to use STIntersects()

I have multiple sets of coordinates in WGS84 and I want to check which polygon each belongs to. My google research have resulted in that I will basically use STIntersects() based on this post: Point-...
0
votes
0answers
9 views

Loading polygon with pop-up box into Mapbox?

I'm having difficulty loading this piece of html code, which would load this polygon into mapbox (which works), but trying to get a pop-up box to give the name of the polyogn when the polygon is ...
0
votes
1answer
19 views

Performing Intersect of polygon with raster, retaining ID of polygons? [closed]

I have a raster data set of land cover and a set of residential addresses (points). I want to find out what percentage of each land cover type is within 1km of each address (i.e. in a 1km buffer ...
0
votes
0answers
31 views

Selecting touching features using QGIS? [duplicate]

There are several ways to select features in QGIS (by rectangle, radius, polygon and expression) but is it also possible to select features, which touches one selected feature? For example: In a ...
-2
votes
1answer
39 views

Stratified random point sampling in Python

I have a very basic knowledge in Python and arcpy. I want to create a stratified random sampling point on a continuous polygon. So far, I have dissolved the polygon (according to categories) and ...
0
votes
1answer
26 views

Exporting Polygons (RGB color bands) nto CSV

I have drawn ~40 polygons over NAIP imagery to collect their R, G, B color bands. I now want to export each polygon with its associated RGB color values into a CSV file so I can plot the polygons ...
2
votes
1answer
41 views

How do I center a polygon on specific co-ordinates?

I need to place a set of polygons onto a set of points, so that each polygon is centered on its corresponding point - any ideas? In MapInfo I can just manually edit the co-ordinates of the center, but ...
0
votes
1answer
20 views

Possibility to use polygon as global area parameter for overpass query

I have been trying to provide a polygon with an array of coordinates as a global parameter for my overpass query. But the query is through syntax error. [bbox:poly:"50.7 7.1 50.7 7.2 50.75 7.15"]; ...
3
votes
1answer
30 views

Filling or splitting polygons proportionally based on variables using QGIS?

I want to divide each country into three separately coloured areas, like this: The proportions of the three coloured areas must based on three columns of attribute data in the country shapefile's ...
1
vote
0answers
21 views

Proportional sizes of polygons QGIS

I was wondering if I can make the polygon with the red arrow bigger than the one with the green arrow based on their difference in size in the attribute table?
0
votes
0answers
22 views

Finding number of points within each respective polygon in table [duplicate]

I have: a shapefile of circles at 15 meters radius and point data with GPS coordinates. How can I count the number of points within each circle and have a raw number that can show such? I've tried ...
0
votes
0answers
58 views

Modeling hole in DEM using QGIS?

I have a DEM raster. I have a polygon representing a hole. How do I combine the two, so that I have a new DEM whose elevation, in the area bounded by the polygon, has been adjusted according to ...
1
vote
2answers
52 views

Converting trajectory to outer edges polygon

Using PostGIS, I'm trying to solve the following problem: I have trajectory data (coordinates from API query), like on this image: and want to convert it into polygon, having only outer edges:
0
votes
1answer
36 views

Rearrange plotorder of SpatialPolygonsDataframe

I have a SpatialPolygonDataframe (loaded with readOGR) I want to plot in either tmap or leaflet. A lot of the polygons are overlapping, and the smaller polygons are completely covered by larger ...
-1
votes
0answers
16 views

Displaying Geometry in descriptive format

I have a SQL view that displays polygon geometry in this format. When I query the view, it displays in this format, and also gives me tab for viewing the spacial results. How can I query the view to ...
0
votes
1answer
54 views

Plot areas by class in a polygon with Google Earth Engine

I would like to plot the number of pixels or the area for each class contained in a polygon (shape of a country). I have found the ui.Chart.image.byClass function but I don't understand how to use it ...
-1
votes
1answer
27 views

Exclude specific GeoJSON data by polygon [closed]

Given geospatial data as GeoJSON, how can I filter this data to exclude geometries within a specified polygon? I need this to work in JavaScript. Example: function filter(featureCollection, ...
0
votes
0answers
14 views

Intersect in poly - only NAs in intersect. Why?

I am trying to intersect a SpatialPolygonsDataframe with a SpatialPointsDataframe. The dataset I want to intersect is quite large which is why I cannot easily make a reproducible code. If anyone could ...
1
vote
3answers
81 views

QGIS: list of coordinates to polygon [duplicate]

In the course of a monitoring exercise for small scale farmers, we captured the coordinates of fields using a GPS tracking in the SurveyCTO app. We used automatic capturing of the coordinates every 5 ...