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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1answer
128 views

Generate territory polygon from sets of points

I'm looking for a simple way to generate contiguous "territories" from sets of points. Say, points A, B and C are in territory 1, and D, E and F are in territory 2, then generate polygons that lie ...
2
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1answer
103 views

Convert Layer to Shapefile without losing Feature definitions

I have created a worldmap with custom defined Features, representing State/Zip-Code sales areas. I want to convert them into a Shapefile, so I can convert the Shapefile into a polygon definition file ...
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1answer
55 views

How do I measure the area difference between polygons in different shp files?

I have couple if shp files with 1000 polygons scattered in them (around 1k in each file) , each shp file represents a time frame (3 months period) and I want to show the a report with a progress of ...
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1answer
55 views

How do I calculate the distance of a segment of line that is inside a polygon?

I would like to calculate the distance of a portion of a line that is inside a polygon, as well as the portion that is outside of the polygon, based on from/to lat/long points on the line, and the ...
2
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2answers
73 views

Check if a polygon is at one elevation

I have a polygon (pond) and I need to ensure it is at one elevation. I have converted all vertices of the polygon to points, used summary statistics to determine the range in elevations and if the ...
1
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1answer
275 views

Convert Multipolygon Geojson to multiple geojson polygons?

I see a lot of questions going from Polygons to MultiPolygon, but is there some easy way to go the other way around? It would also be useful to preserve the attributes from the MultiPolygon to apply ...
3
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0answers
65 views

What is the area that OGR extracts from the (geometry) shp files for polygons?

The ESRI July 1998 technical documentation for polygon shapefiles at page 10 makes no mention of either area measures or length measures (apart from byte/record-layout matters). Yet OGR enables me to ...
2
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2answers
86 views

Editing a Single Polygon Outline

Mapping geological contacts often needs true contact and inferred contact. I would like to know if it is possible to divide a single polygon outline which marks the outline of a granite body, so that ...
3
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0answers
52 views

Algorithm to find the boundary grid points [duplicate]

Let us consider a set S consisting of a collection of grid locations (i,j),i,j=1,\ldots,n, in 2-dimensional gridded plane. Here the point (i,j) corresponds to a rectangular grid in the X-Y plane. ...
3
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0answers
72 views

Dilating a polygon by a circle sector

I want to dilate a polygon by a circle sector in ArcMap. Because my python skills are not that good to figure out how I can use the R prototype of How to create an oriented buffer using arcpy? . Is ...
3
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3answers
84 views

How do I draw smooth vertexes around curves in ArcMap 10+?

I have some polygon layers (parcels) that have vertexes drawn around curves, as if traced. How do I click and drag to draw vertexes in a smooth shape? Big difference between what was originally there, ...
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1answer
35 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 ...
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1answer
126 views

Need to quickly know (CLI) whether point lies inside polygon

in my app I am parsing an XML from the web which gives me such coordinate info: I am able to use my app to get a pair of float values like 14.871381 and 50.065968. I do not want any complicate ...
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0answers
39 views

How to find the the boundary co-ordinates from a given set of coordiantes? [duplicate]

How to find the the boundary co-ordinates from a given set of co-ordiantes? I understand that this question asked previously and answered here How to find the boundary co-ordinates from a given set ...
2
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5answers
293 views

Make a polygon out of a polygon's hole?

I have a large polygon with many vertices that has a hole in its center. I want a polygon of the hole, the empty space. How can I easily do that? (It is much too complicated to digitize easily)
2
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3answers
153 views

Removing small polygons gaps in a Shapely polygon

I know this issue has been addressed before with different software, but I am looking for an approach with Shapely. I have a polygon with a very small gap on the interior of the shape: Here is a ...
1
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1answer
59 views

Cutting polygons into smaller (more regular shape) chunks

I came up with a polygon shapefile like what you see here. There are some small polygons which exactly match what I want, though I want to cut(split) those bigger ones into smaller pieces. So far I ...
1
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0answers
108 views

Invalid join selectivity error in postgis 2.1.3

I have 2 tables, one for points and one for polygons. I want to find points falling within theese polygons, so I quered: select p.id, l.id from points p inner join polys l on st_contains(l.geom, ...
2
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1answer
53 views

Join attributes from multiple polygons to an overlaying polygon

I have a polygon-shapefile, containing 562 single features (feeding -layer). I want to add their attributes to an overlapping polygon-layer (bear_buffer -layer), containing 1330 features. The ...
1
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2answers
120 views

How to draw polygons in shapefiles

I've hit a snag and realize this is probably a very simple and basic question, but how do I draw a polygon in a shapefile that I've created from joined points of 2 .csv files? Which specific tool do I ...
2
votes
2answers
86 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 ...
1
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1answer
61 views

IdentifyTask for “hollow” polygon (using ArcGIS API for JavaScript)

I have a web map application set up that's currently testing on a variety of Dynamic Map Service layer types, including points, lines, and polygons. This application includes a tool that makes use of ...
0
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1answer
92 views

OpenLayers: showing polygon within donut hole

I Am using OpenLayers 2.13.1 to display Zip-areas. I have a postGIS database with multi-polygons, that I show on a map. The user can select / deselected them. Some polygons have an area (I think they ...
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0answers
56 views

QGIS 2.4.0 doesn't support multiple types of geometry in GML file

I'm testing GML 3.2.1 data according to INSPIRE Data specification (version 3.0). Data for theme Cadastral Parcels shall have both polygon geometry and definition point. When I download data from my ...
2
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1answer
79 views

Polygon files corresponding to Russian Census

My team is using the 2010 Russian Census and we'd like to have polygons that correspond to these population values. We're flexible to any sort of polygon format (shapefiles, GeoJSON, KML, etc). ...
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1answer
163 views

clipping two SpatialPolygons : Error in RGEOSBinTopoFunc

I want to clip two SpatialPolygons on R without success, I followed the article in the disscution How to perform a true GIS clip of polygons layer using a polygon layer in R? Polygone 01 : > ...
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2answers
155 views

Count the number of points in a (multi)polygon in shapely?

I'm using Python, Shapely and Fiona to process some shapefiles. Is there an easy way to count the number of points in a polygon/multipolygon in Shapely and Fiona?
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0answers
41 views

How to use GIS data with CGAL?

I read a few posts here at GIS.SE that points to useful algorithms in CGAL. I'd like to test algorithms in CGAL such as medial axis transformation/polygon skeleton extraction, but the examples on the ...
1
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1answer
69 views

Convert raster to polygon based on cell value ranges using ArcGIS for Desktop?

I have a floating point-valued raster which I need to convert to polygon as follows Put the cells with VALUE < 0.5 into (a small/the smallest number of) polygons Cells in the range [0.5, 1] into ...
4
votes
2answers
492 views

Order of polygon vertices in general GIS: clockwise or counterclockwise

Two days ago I asked a question about the internal storing order for the vertices of a polygon in ESRI shapefiles. That question was answered (Are polygons stored clockwise or counterclockwise in a ...
1
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2answers
220 views

How to draw a polygon given a distance and bearing in QGIS

Apologies if this question has been asked before I'm not come across it. I want to draw a polygon given a length and a bearing, basically a square with lenght 1m. I cant seem to manage it with the ...
1
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1answer
57 views

How to add IDs of the links composing a polygon?

I built up a polygon layer from a road network for finding roundabouts using the compactness factor of a polygon. Then I have to intersect the extracted roundabout polygons with the road network so ...
3
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0answers
75 views

Geoprocessing tool for finding specific point within polygon

I have a ArcGIS task and cannot find a solution. I try to find a certain point within a polygon (see picture). This example is handmade and I need a geoprocessing solution I point I try to get is ...
0
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1answer
64 views

Add Marker on the polygons' centre using Openlayers?

I have written a code to draw polygon from the WKT format.Now I need to add the marker at its centre. In the following code I have passed the centre and shape in WKT format(extracted from database). ...
2
votes
2answers
174 views

Can't transform lines to polygons

I have a similar question to: How to join lines in QGIS for later using "lines to poly"? I have a line shapefile that I wish to transform into a polygon shapefile. After making some ...
1
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1answer
346 views

How can I convert GeoJSON with multiple Polygons and MultiPolygons into single MultiPolygon?

Is this even possible? I have a GeoJSON file with multiple polygons and multipolygons, and I need to set styling on them (in Leaflet.js). I'd like to create a single, large MultiPolygon from the ...
1
vote
1answer
101 views

How to clear areas outside map in R

I succeeded thanks to the eblonde in the disscution (problem with polygon smoothing in R) to smoothing polygons in R. Code: inter1= read.table("c:/inter2.csv", header=TRUE) #add a category ...
3
votes
2answers
564 views

Merge geojson polygons with WGS84 coordinate

I have a Geojson file with some adjacent polygons and I want to merge them into one. I know it's a recurrent question but I can't find information for polygons with latitude and longitude coordinates ...
1
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1answer
259 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. ...
3
votes
3answers
245 views

How to count the sides or edges of a polygon?

I wondered if it is possible to determine the number of sides / edges (not vertices) that a polygon has. Imagine the following case. There is a shapefile with 10 polygons. Is there any way to ...
3
votes
1answer
212 views

problem with polygon smoothing in R

With R I am looking to smooth my Polygon: inter2.csv code: inter1 <- read.table("c:/inter2.csv", header=TRUE) # add a category (required for later rasterizing/polygonizing) inter1 <- ...
3
votes
1answer
391 views

Polygon fill colour specified by column R spplot

I am trying to plot a geological map using the spplot function in R. For every unit I already assigned a specific color in the col-column of the SpatialPolygonsDataFrame. Now I would like to plot the ...
2
votes
1answer
51 views

SQL Server equivelent to Arcmap Intersect for polygons?

I have three different sets of GEOMETRY Polygon datasets in SQL Server that completely overlap. I need to create a new dataset that has a polygon for each unique area of the three layers. So ...
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0answers
36 views

Map polygon property in one shapefile to polygons in another shapefile with same outer boundary

I have two shapefiles covering a region with the same outer boundary. The polygon shape coverage (tesselation) of the two is different. One file (A) has a property assigned to each polygon. How do I ...
2
votes
1answer
258 views

Count overlapping polygons in single shape file with R

I have a shapefile of species ranges for ~ 346 species. Some species have multiple polygon ranges so there are 1,078 polygons and many polygons are multi-part. It looks something like this: I ...
2
votes
1answer
252 views

create polygons and fishnets of specific size and orientation and buffers

I want to study 6 areas in the field and in order to do so I want to divide each one of them into smaller areas/parts. What I would like to do is find an average square or rectangle area surface ...
9
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1answer
199 views

Cutting out the world into polygons of equal population size

I would like to cut out the world into polygons of equal population size, say 100 million persons (starting for example with raster data of population density as provided by the NASA). I know that ...
1
vote
1answer
168 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 ...
2
votes
1answer
80 views

Create a custom Identify dialog

How can I check if a point belongs to a polygon? I want to create a custom identify tool with edit option. I am using C# and ArcMap 10. My idea is to click on the polygon (building/park/etc) in ...
2
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0answers
97 views

Merge vector layers to fill gaps in QGIS

I have a zip code map which I added per zip code data too (a regional director for each zipcode), and then dissolved the map based on the director attribute. As you may or may not know, zip codes are ...