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.

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3
votes
1answer
418 views

Cutting polygon using line - cutter, cut() - using ArcPy?

What I'd like to do, using ArcPy: use a line to split a bunch of polygons into separate parts. Here is what the inputs could look like: In this case the line should split each polygon into two ...
1
vote
1answer
167 views

How to get the coordinates inside the polygon using python

I have a polygon and using this code snippet we can get the coordinates boundary of the polygon. canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.currentLayer() coord = ...
1
vote
2answers
1k views

Select points from a table that exist in a custom polygon

We have a property search site where the user draws a polygon on a map and then the app displays all properties that fall within the polygon. We have properties stored within a Postgres table that ...
4
votes
1answer
80 views

How to find the distance from a point to a polygon, via another point, in R

I am trying to calculate the distances between a central point, and the edge of a polygon, along straight lines drawn between the central point and another set of points (where necessary extended ...
5
votes
1answer
2k views

How to automate the drawing of polygons (square) around a number of points in QGIS?

In QGIS (or alternatively any other scripting + GIS stack), how can I automate drawing a 100km x 100km square around a number of points, with the point being dead in the center? I'd need to loop ...
0
votes
3answers
2k views

How to get WKT or GEOJson by country or city name with Overpass API?

I'm trying to understand Overpass API, I'm experimenting with it, but cannot get what I expect. Overpass API doesn't return me neither polygon shapes, nor WKT, nor GEOJson, nor even a highlight of the ...
0
votes
3answers
510 views

How to generate polygons upto the edge of other polygons?

I am doing some work on a pipe network (blue lines) and I am trying to attribute the information about the street to the pipes. I have 2 polygon layers one of the blocks (green hatch) and one of ...
1
vote
1answer
144 views

How to get polygon distance from a route?

I need to calculate the location of polygons along the route in ArcGIS (ArcInfo) 9 or 10. What I have already found out is only the calculation of the start and end of the intersection of a polygon ...
2
votes
0answers
112 views

Placing a label based on a point's location within a polygon

I have a polygon dataset and a point data set with occupants. I need to label the occupants of the house within the polygon and need the label to show up on the side associated with its polygon. ...
2
votes
2answers
113 views

Add overlapping polygons

I have a feature class that contain many overlapping polygons. Each polygon has a field value which I would like to add together wherever the polygons overlap. There are about 100 polygons each with ...
1
vote
1answer
126 views

finding the nearest point along the edge of a polygon

I have a polygon shapefile which represents a study area (island). I also have a point shapefile representing some villages. What I am after is to locate for each village point the nearest point along ...
2
votes
0answers
75 views

Merge Spatial polygons from shapefiles

I have downloaded the shapefiles from the following website: http://download.geofabrik.de/europe/france.html Each zip contains a "landuse" shapefile and I want to merge all of them in one single ...
0
votes
1answer
89 views

delete unconnected polygons in a shapefile [duplicate]

I need to delete isolated polygon (green circle) from a shapefile but I do not want to delete polygon that connected with other polygon (red circle?
0
votes
2answers
284 views

How to combine multiple zipcode polygons into one polygon

In CartoDB, we have a table of chapters that make up a national organization. Each chapter record has a polygon that defines the geographical area that the chapter covers. The area a chapter covers ...
1
vote
0answers
128 views

PostGIS: intersection of a polygon with 2 rasters

I'm trying to get the intersection of a Polygon with 2 raster layers in PostGIS. The rasters have the same size and pixel size and I'd like to retrieve for the polygon a list of something like that: ...
2
votes
4answers
8k views

Understanding the polygon handler function in Openlayers

Using openlayers, I want to be able to draw one polygon on a map. After one polygon is drawn, I want an event to fire that stops any more from being drawn until a button is pressed. My current code ...
1
vote
0answers
87 views

Query to merge simplified polygons according to the map scale-factor

I'm trying to construct a view in PostgreSQL that simplify polygons according to the map scale-factor. Basically I was reading this thread ...
0
votes
1answer
244 views

Draw polygon with GUI

I'm looking to make a python add in tool for ArcMap to draw a polygon. Eventually I want the tool to also calculate the area and a bunch of other things but for now I would be happy just drawing an ...
2
votes
1answer
772 views

Split polygon into several smaller polygons in QGIS

I have a layer of polygons depicting response boundaries, I would like to break each of these polygons into a number of sub-polygons. As this is for an exploratory project, the polygons themselves ...
2
votes
2answers
1k views

Converting polygon layer to *.txt files using ArcGIS Desktop?

Is there any way to convert polygons that do not have coordinates in the attribute table to a txt file with coordinates. I will be using the txt file in a different software (not ArcGIS), so I need ...
0
votes
0answers
15 views

How do I search for features within a polygon in EarthExplorer or other freely available tool?

In USGS EarthExplorer, I'm trying to search for cemeteries within a defined area using a polygon created in Google Earth. If I select cemeteries under features, it clears that selection when I load ...
1
vote
4answers
2k views

Finding polygons which are within/intersect other polygons using FME?

Version: FME Desktop 2014 SP3 I have two shapes with polygons. Now i want to locate those polygons of shape A (polygon.shp) which intersects polygons of Shape B (POLYGONS) (or are within them). I am ...
17
votes
6answers
9k views

Generate points that lie inside polygon

I have polygon feature and want to be able to generate points inside it. I need this for one classification task. Generating random points until one is inside the polygon wouldn't work because it's ...
1
vote
0answers
83 views

XYZ bounding box of a spherical polygon

I'm looking for an algorithm to calculate the 3d bounding box of a spherical polygon - i.e. the min/max X, Y and Z over that part of the surface of a unit sphere. The purpose is to aid fast ...
0
votes
3answers
105 views

Make polygon from area not covered by loaded polygons (like invert selection)

See screenshot, from geojson.io, with a geojson file loaded: So how do we make a polygon out of the blank area? Looking for a way which doesn't involve manually copying selected sequences of ...
9
votes
1answer
4k views

Polygon label repeated for each tile

I'm using the standalone GeoWebCache to serv tiles from a remote GeoServer. My problem is that the polygon label is added to each one of the tiles served, instead of only once in the polygon centroid. ...
1
vote
0answers
44 views

Lines > Polygon artifacts

I am trying to make polygons from a set of boundaries from an SVG file with closed polylines I downloaded off wikipedia. 1) convert SVG to DXF via Inkscape 2) import into QGIS (shows polyline data) ...
0
votes
2answers
491 views

Problems with Polygon Reshape Feature [closed]

I've created a polygon and closed my project, after opening the project again, i can't use the Reshape Feature tool in that specific polygon. But if I create a new polygon in the same shapefile I can ...
1
vote
0answers
50 views

Shaded KML overlays on OSM tiles in QGIS?

This seems simple - but the solution is escaping me. I have a series of dynamically generated KML files describing simple, shaded polygons, with each polygon having a slightly different (externally ...
1
vote
0answers
57 views

Polygons in Polygons

I have 2 layers, they represent 2 different data. I did a spatial join to see the polygons that fall in the other layer using the match option as identical. Before, i used the intersect as the match ...
0
votes
0answers
17 views

Cut polygon with polygon QGIS [duplicate]

I have two polygons. One sits mostly within the other (pink) and I would like to cut this from the other polygon (blue). This is a feature I have used before in MapInfo but struggling to find the ...
0
votes
0answers
28 views

Dynamic polygons grid with specified area based on raster

I'm interested if anyone have idea how to automatically create (maybe in R?) dynamic grid of polygons with specified approx. area (for example around 20000 m2) based raster data or points with values ...
3
votes
3answers
333 views

How to change 0,360 WKT string to -180,180?

I'm reading POLYGON WKT strings using OpenLayers.Format.WKT().read(). The polygons use 0,360 longitudes but my map is -180,180. When I display the polygons on the map they are displayed outside of the ...
6
votes
2answers
1k views

How to combine data from overlapping polygons?

Here's what I'm working with: Shapefile of the current 32 Congressional districts for all states Shapefile of the tract boundaries for Texas A DBF format table of Hispanic counts and proportions for ...
3
votes
5answers
3k views

Counting road intersections and blocks

I have a shp file that consists of the road system of Mexico City. I would like to count the number of road intersections (crossings) and blocks (which I would define as a segment starting from one ...
0
votes
0answers
23 views

Finding how many points are in polygon of layer in specific time using QGIS?

I have the layer that I created with the number of earthquakes in each region in the last 400 years. I want to know the number of earthquakes that occurred in one specific region prior to 1900. How ...
3
votes
1answer
377 views

Area-weighted rasterising of polygon data

I'm looking for any GIS tool to do detailed rasterising of polygons. I've checked GDAL's gdal_rasterize command (and API), and ArcGIS's Polygon to Raster tool, but they only rasterise 1 attribute per ...
0
votes
1answer
34 views

Double Entries/ Errors with Digitizing Polygons

I have a layer that has errors, i mean polygons have double entries (digitized twice), i can edit manually but there's a lot of attributes and it will take ages to clean the data. Is there any short ...
0
votes
2answers
379 views

Get Area size using Dragbox in Openlayers 3

I need to be able to show the square meters of an area using dragbox. There's a great example using draw polygon, but I need to limit users to a regular rectangle. The formulas and SHOULD be the ...
1
vote
1answer
115 views

Make diagonal grid in QGIS, divide square into squares

I have square polygon which is aligned under some degree and I want to divide this square to, for example, 25 smaller squares, which must be under the same degree in this square polygon. How this can ...
1
vote
0answers
18 views

calculating total area of multiple polygons in qgis [duplicate]

I wish to know the total area of all polygons within a shapefile layer. So far I have added a new column to the attribute table that shows me the individual area of the polygons.I tried to copy the ...
2
votes
3answers
208 views

Find closest point between polygons inside other polygon

I have access to ArcInfo (ArcGIS 10.1). The dark polygons are settlements. The green polygon is derived from a suitability analysis. The surrounding white area is restricted. I want to find a point ...
5
votes
1answer
851 views

Leaflet JS add GeoJSON shape as a hole in a polygon

I have a dataset which already contains geojson. I can add it to my map with the following line of code. L.geoJson(data.geojson).addTo(map); And I get this But I want to achieve this, where the ...
5
votes
1answer
2k views

Extracting intersection areas in R

I have two polygons. One contains fields(X,Y,Z) and the other contains soil types (A,B,C,D). I want to know what area of every field contains which type of soil. I tried the following: ...
1
vote
1answer
31 views

Workflow for updating raster using polygons of different attributes

I require a specific output but it is proving difficult for me to work out a workflow. I have: 1) polygons of new housing developments (356, non overlapping) 2) a 25m raster of land cover I want ...
1
vote
0answers
19 views

Overlapping polygons: how to sum attribute values for areas where multiple polgons overlap [duplicate]

I have what seems to be a fairly simple problem but I cannot find a solution. Any help would be much appreciated. I am working in QGIS 2.8.1. I have a shapefile of polygons, each of which has a ...
1
vote
1answer
230 views

Order a list of points to make a polygon with smooth outer border

I have a function that pulls some lat/longs from a Database and then I put those values in a polygon to see it's shape. The problem is they are so random in position and direction from each other that ...
17
votes
3answers
6k views

Proper way to rbind SpatialPolygonsDataFrames with identical polygon IDs?

What's the proper R idiom for rbinding SPDFs together when the IDs overlap? Note that here (as is often the case) the IDs are basically meaningless so it's pretty annoying that I can't just make ...
1
vote
1answer
118 views

Country border between two points

I am trying to extract country borders between two points, using Python. The border is a Shapely Polygon.exterior or LinearRing, the start and end points are Shapely Points. My idea is the following: ...
0
votes
0answers
46 views

How to arrange polygon in Postgis

I have a lot of polygons in a Postgres database. I want to show the polygons, but in order of the the biggest to the smallest. I used the following code: SELECT ST_Area(area_polygon) as luas FROM ...