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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0
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3answers
12 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
3k 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
15 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
155 views

Zipcode to Polygon/Boundry

Is there any API out there which can give me Polygon value for a zipcode? I really thought that it would be fairly easy for me given the number of Maps APIs out there. Either Google Maps API or ...
0
votes
2answers
249 views

Problems with Polygon Reshape Feature [on hold]

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 ...
0
votes
2answers
259 views

Calculating minimum/maximum width for overlay of two polygon strips in ArcGIS or some Opensource GIS

Is there some solution for calculating minimum and maximum width for overlay of two polygon strips? When I clip these strips the result is another strip with variable width about 1 km and 20 km long. ...
1
vote
0answers
15 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
37 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
1answer
784 views

How to narrow the result from Nominatim with only cities and countries, no additional areas with the same name?

I'm trying to get WKT or GeoJson polygons of cities and countries from Nominatim (for example, Paris and France). I send a GET request but it returns me several results named "Paris" or "France". How ...
0
votes
0answers
13 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
12 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 ...
0
votes
2answers
1k views

How to get a list of OSM relations (id numbers) of cities and countries only?

I want to get OSM polygon shapes (GEOJson or WKT) of countries and cities only. I know that it is called a "relation" in OSM and each relation has its own id (New York is 175905, for example). How may ...
3
votes
3answers
269 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 ...
0
votes
2answers
50 views

Extracting multiple values of raster to polygons using ArcGIS for Desktop?

I was hoping I could get some help on how to extract information from a land use raster using polygons. I have a layer with 157 polygons and a land use raster with multiple land use categories for the ...
5
votes
2answers
851 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 ...
1
vote
1answer
50 views

How can I eliminate leftover border/boundary in QGIS?

I am trying to generate a shapefile which contains the unincorporated areas of St. Louis County, Missouri. I'm using two shapefiles: St. Louis County from the 2012 census, followed by St. Louis ...
2
votes
5answers
2k 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
21 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
273 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
20 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
56 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
37 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 ...
2
votes
1answer
153 views

neighborhood boundaries for Saudi Arabia

I currently have set of coordinates (lat,lon) that I would like to associate with neighborhoods or districts in Saudi Arabia. Therefore,I might be looking for neighborhood boundaries (polygons ...
0
votes
0answers
14 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
139 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 ...
3
votes
1answer
56 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 ...
2
votes
1answer
81 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: ...
10
votes
8answers
19k views

Get boundary of raster image as polygon in ArcGIS Desktop?

I have a rectangular raster image in ArcGIS. My question is: how can I produce a polygon which is just the extent of the raster image? That is, I want to have a polygon layer with a single ...
1
vote
1answer
23 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
2k views

How to write a point-in-polygon query for Postgis?

I'm trying to write a query in Postgis which will return all rows where a dynamically changing longitude/latitude point resides within the geometric polygon of that row (in the geom column). This is ...
2
votes
1answer
165 views

Dynamically drawing a polygon around another shapefile, ArcGIS 10.2

Let's say I have a vegetation raster that indicates the density of forest all over the world. I also have a shapefile that contains the admin boundaries of each country in the world. The easy part is ...
1
vote
0answers
14 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
51 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 ...
1
vote
2answers
219 views

How to resample polygon vertices so that they are evenly spaced in Arc 10

I have digitized the outline of many river channels (by both manually picking points and using streaming mode), but now I need the vertices to be evenly spaced (for input to another program). I tried ...
11
votes
3answers
3k 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
45 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
33 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 ...
1
vote
0answers
25 views

Splitting up a single polygon into many polygons of equal point count

I have point data split into 15 different values and want to split up the (green) polygon into a number of smaller polygons each containing the same number of points so that I can make a chloropleth ...
4
votes
1answer
289 views

Validating polygons for no gaps/overlaps/slivers using ArcGIS Desktop?

I would like to assess the spatial accuracy of a load of polygon shapefiles which are supposed to show air quality for a bunch of countries. Firstly I want to assess whether each shapefile has a ...
7
votes
4answers
27k views

How to create polygons from lines?

I am trying to create polygons from a line layer of lots and concessions (large blocks of land in rural areas). The lines are mainly grid style as they intersect mostly at right angles. I need to ...
1
vote
1answer
206 views

Is it possible to draw polygons along Google Maps Polyline?

Web application has option that user draws polyline on Google Map. After he draws it, there is a button 'Add polygons', which should draw polygons along that line, based on some width and height in ...
0
votes
1answer
40 views

Getting the max value from where polygons intersect in MapInfo

I am trying to do an intersect query on two polygon layers in MapInfo. One is a buildings layer and the other are 2d mesh triangles. I want to get the max depth from any of the triangles that ...
1
vote
1answer
352 views

Summarize polygon area using another polygon

I have a shapefile representing public/private lands in Montana. This is a multipart shapefile where I've simplified attributes so that #1==private and #0==public. Next I have a shapefile of ...
0
votes
0answers
39 views

summarize multipart feature by another multipart feature

I have one shapefile with many polygons, each representing the area of a selection of crops. I would like to determine the total area of each crop by county using a shapefile of counties in Arcgis ...
1
vote
1answer
61 views

ST_Intersection for polygons

I'm looking for a query that returns overlapping areas of two tables with polygon geometries. Using row_number() over() the entries of the gid column are not unique in the case of dumped ...
6
votes
2answers
164 views

Summing up over area based on distance related function?

Through a field study, we learned that the density of a bird species in the forest was related to the distance to forest edge: ln(density) = 1.89*(distance to edge) + 0.34 Now, for any forest ...
1
vote
1answer
173 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 ...
1
vote
3answers
620 views

How to create one KML per polygon (from one Shapefile)?

I have a shapefile containing hundreds of polygons. I need to create a kml of each of the polygon. Is there any way that I may not have to deal each polygon individually and my polygon file may give ...
12
votes
7answers
23k views

Extract coordinates of polygon vertices in ArcMap 10?

I've got about a dozen polygons in a feature class loaded in ArcMap 10, all in geographic WGS 1984. How do I easily obtain the coordinates associated with each vertex of each polygon in that feature ...
2
votes
1answer
318 views

Determine when I have crossed state line?

We are currently using the Google Maps API to get route information and total mileage but we would like to determine when we are crossing into a new state. When we return the route information we can ...