Process of creating geometric polygon features.

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2answers
52 views

QGIS - Create equal length polygon along polyline

How can I create a series of polygons along a line? I need to assess the density of a number of targets along a line within a corridor. I have tried the following: creating a buffer, using the ...
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1answer
32 views

Defining polygons based on thickness maps using ArcGIS for Desktop?

I want to find and create polygons that demarcates three different inflection points in a thickness raster: where the thickness start to increase, where the thickness is at its max and where it starts ...
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1answer
84 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 ...
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1answer
82 views

How to copy closed loop lines into polygon feature class

I'm trying to utilize line contour data to find the volumes of local depressions. To do this, I want to copy the closed loops formed by depression contours into a polygon feature class to find the ...
3
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0answers
196 views

Postgis - extrude a polygon

I want to extrude a polygon shape in postgis to create a pseudo 3D effect. To this end I have written a crude function to achieve it. This is very much test code and it creates a new Y vertice for ...
3
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0answers
186 views

building larger polygons from smaller ones *without* a common id in PostGIS

I am looking for a means, using PostGIS, of reconstituting a set of polygons from tens of thousands of smaller polygon 'pieces'. This is a simplified example, with the pieces shaded: Unfortunately ...
2
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0answers
34 views

How to split a polygon into quadrants in R/Qgis?

I am solving the same problem as How to split a polygon into quadrants?, except that I am looking for a solution in R or QGis. So I have a polygon layer shapefile, which is unfortunatelly not exactly ...
2
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0answers
76 views

How to extract polygons from a road network?

I need to extract faces (or polygons) from my road network and calculate their areas. I mainly use Arcpy packages but even if you know it in QGIS APIs, I'd appreciate if you'd share it with me. If it ...
2
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0answers
63 views

Weird-looking France after OSM import with osm2pgsql

After importing france-latest.osm from Geofabrik, using osm2pgsql, it seems that the polygon attributed to Metropolitan France (osm_id = 1403916) is a bit odd: I'm far to be a geography expert, but ...
2
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0answers
279 views

Right click editing menu disabled arcgis 10.0

Editing Polygon feature in FGDB, Create Features, Click Rectangle (in Construction tools), right click, unable to select any options (Absolute X, Y / Direction / Length) from popup menu. Help? Havn't ...
2
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0answers
174 views

How to add address block on Google Mapmaker?

Is it possible to mark a block of addresses for example B-block, xyz colony, which is a logical block of addresses on Google Mapmaker? If possible, how do I do it? I want to add a polygon feature ...
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0answers
29 views

Geoserver does not render polygon properly

I am trying to a get polygon layer from CSV file. I chose to do it via rasterization and polygonization in QGIS, howerver, Geoserver has problems to correctly render some polygons. This is how the ...
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0answers
28 views

Network Analyst Add City Boundary as Polygon Restriction

I have a network I am trying to create but am finding the service area polygon I create are "leaking" outside of the city boundary. I was curious if there was a way to add the polygon as a restriction ...
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0answers
54 views

Collection of polygons from a collection of points

I have a set of points, spread over a wide geographical area. I need to be able to create a set of polygons which best represent the clustered points. And I would like to create the clusters based on ...
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0answers
385 views

Topography: How to convert raster into vector layers?

(nb:This project is part of the #Wikipedia #wikimaps project) 1. Question: How to create vector topographic maps from raster image ? How to convert raster topographic image into closed vector ...
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0answers
142 views

Problems combining (union) Multipolygons in geodjango

I'm using geodjango and postgis (1.x), What is the best way to combine (union) a list of multipolygons. in what i assume is rather inefficient i'm looping trough like this combined = multipolygon ...
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0answers
274 views

Spatial Reference and Area/Length Attributes relationship

I currently allow users to add a shape file in. From the shape file, allow the user to generate a new layer base on the polygons from the shape file's polygon they imported. Generating the new ...
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0answers
58 views

Dividing a polygon into certain areas (open source solution preferred)

I have a polygon with an area of 50.000m². Now i want to devide this area in two polygons of different areas with a line layer. The left polygon should have an area of 30.000m² and the right polygon ...
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50 views

“Flood fill” polygon capture mechanisms in various GIS

Within our organisation we have a requirement to capture lines dividing land into chunks and then to create polygon features using aggregates of these divisions. In the example image below ...
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0answers
15 views

creating Polygon from LineString and a width

I have to create a Polygon from a lineString and a width. Ex: Given a street as a lineString (Or a list of points) and a width, create the polygon (the road). I am using Geotools, but I couldn't find ...
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0answers
99 views

How do I optimize the speed and enable ArcGIS to create the Service Area around my locations?

The Problem: Every time I try to solve the service area around locations, ArcGIS crashes. It takes forever to load facilities and draw just a single polygon. How do I optimize the speed and enable ...
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0answers
121 views

How to draw polygons around known clusters

I need to split up an area into non-overlapping, but contiguous territories. I have n points on a map, which are partitioned into k sets. The partition is only partially geographic, meaning that ...
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0answers
479 views

Why is a Shape polygon file not editable?

I received a .shp polygon file. When I choose the edit toggle tool in QGIS the little red X's appear as expected. Then when I try to edit the polygons such as add a polygon all seems to go well, when ...