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
2answers
146 views

QuickOSM returns no result

I am trying to download the polygons for the Umweltzone Heidelberg from OpenStreetMap using QuickOSM in QGIS. I queried by name as shown in the screenshot: The corresponding OSM script looks like ...
0
votes
2answers
78 views

How to Dissolve Polygons Inside a Feature Class Based on Attribute Conditions

I have a large shapefile (saleArea.shp) which includes hundreds of small adjacent polygons. I would like to dissolve the polygons based on some conditions from tValues field into 5 bigger groups like ...
1
vote
0answers
99 views

How to show two layers at the same time in Qgis

I have a question about Qgis layers. I want to see two layers at the same times. one is lines which are boundary lines and the other is polygon which are district. when i was surfing about this ...
1
vote
1answer
75 views

Extracting the closest Point to a Line within a Polygon using ArcGIS for Desktop

I have the following shapefiles: Polyline: Detailing a road network. Polygon: Containing approx. 2000 polygons enclosing sections of that road network. Point: Containing numerous (OS Addressbase) ...
5
votes
3answers
3k views

How to interpolate into polygons using ArcGIS Desktop?

I need to interpolate values from points to polygons. I have a point shapefile and a shapefile of adjacent polygons. Some polygons get several points falling inside, some have nothing. I thought ...
1
vote
0answers
139 views

Changing Polygon shape on Zoom in and Zoom out in google maps using javascript

In my application iam using google maps v3, on page load with default zoom level of 15 i load few polygons by passing points(latlng coordinates) from database on the google map now my question is when ...
4
votes
1answer
99 views

Creating shapefiles using textfiles in QGIS

I have a shapefile in QGIS which has polygons in it . There are several other attributes for each feature . I want to add another attribute to each feature . The value for this attribute is available ...
1
vote
1answer
149 views

Performance Improvement of Postgres vs PostGIS

I am trying to run the following query thousands of times per second to determine which is any polygon contains the passed in point. SELECT * from areas WHERE poly @> ? Poly is the name of the ...
0
votes
1answer
200 views

Multipolygon From Multilinestring PostGis

I have been looking for a answer for days. I dont even know if its possible. Tried: ST_AsGeoJson(ST_MakePolygon(ST_transform(geom,4326))) ERROR: Shell is not a line ST_Polygonize(ST_LineMerge(...
2
votes
1answer
164 views

Convert Postgresql Polygon to PostGIS POLYGON

I have an existing table in postgres which contains a plain old posgresql polygon. I have added a new column using SELECT AddGeometryColumn ('public','fences','geom',4326,'POLYGON',2); I would ...
1
vote
0answers
24 views

Collect near polygons [closed]

I have the following data: The data have 5 level (in tones blue). I want to collect only the nearest polygons with the same level and sum the number (represent client number). When I collect only ...
0
votes
0answers
26 views

how to use st_intersection() with re-projection in POSTGIS?

This is a shipping route from 'portland to busan' and I want to check the route against land_polygons like how much distance is traveled by a route through land.And the problem is while checking the ...
2
votes
1answer
164 views

CartoCSS: labels along inside of polygon boundary

I'm using CartoCSS to render maps that include large polygons (like national parks). At higher zoom levels I want labels along the inside of the polygon boundaries, like in OpenStreetMap: I ...
4
votes
1answer
6k views

Creating polygon based on spatial extent in ArcGIS Desktop?

Is there anyway that I can input: The Coordinates System (projected is OK) The bounding box and create a rectangle polygon based on these?
2
votes
1answer
216 views

Difference between intersect {raster} and gIntersection {rgeos} in polygons - R?

I am interested in knowing the difference between tools: intersect {raster} and gIntersection {rgeos}** tools in R. I have several overlapping polygons and I am interested in their overlap, but mostly ...
0
votes
1answer
68 views

Clip lines by overlapping polygons

I want to cut a line shape into parts by polygon areas. No problem so far. But the polygons overlaps each other at the border. I need one line result for the whole area of every polygon. Any ideas for ...
0
votes
2answers
195 views

PostGIS Multipolygon - holes

I have MULTIPOLYGON in my PostGIS database to store countries (with islands etc.). But I need to add holes to my borders for lakes. How can I store multipolygon with holes? I am using ST_SetSRID(...
1
vote
1answer
36 views

How can I assign an object in a shapefile to a location based on another shapefile?

I have two different shapefiles to work with: one of them has polygons representing tree canopy data and the other is a shapefile for census tracts in the area I am working on. I am trying to figure ...
0
votes
0answers
14 views

Donot Polygon in QGIS [duplicate]

When I am creating a polygon inside of another polygon, both the polygons are selected, Please help me to create donot polygon in QGIS.
1
vote
0answers
85 views

QGIS split line into segments on polygon

Is it possible in QGIS to split a line into segments given which polygon it falls within? I am using 2.8. For example, a line that passes through three polygons will become three separate lines. Each ...
6
votes
3answers
4k views

Easily calculate “roundness/compactness” of a polygon

I am trying to find ways to quantitatively describe the shapes of various polygons. For my project, these polygons represent lakes, rivers, lagoons, and parks. So they can be almost any shape. One ...
5
votes
3answers
946 views

Creating map with same-area hexagonal polygons using ArcGIS for Desktop?

I'm trying to figure out (1) what this type of map linked here is called (I've been unable to find the name through search), and (2) whether there is an Arc tool that will transform a shapefile or ...
1
vote
0answers
49 views

Enable editing only one feature in a Polygon Layer using PyQGIS

I was thinking of locking neighboring polygons (parcels) by disabling editing on them, while editing would be possible on the polygon at the center. This means other polygons can also be edited in ...
0
votes
0answers
11 views

Divide/Split single polygons from one Shapefile using ArcGIS for Desktop? [duplicate]

I have a map of Austria which shows all the federal states in own polygons. As a whole - sure - you get Austria. I know how to make several states invisible so that you can just see particular states ...
4
votes
1answer
270 views

How to map flood areas from a set of points containing surface and height of water?

I am working on the damages made by the typhoon Haiyan. I use QGIS 2.0 with extensions and toolbox, and MapInfo. I have vectors, rasters of the place. I want to map the flood area along the ...
1
vote
1answer
272 views

Elevation data from 3D shapefile of buildings to raster DEM

I have acquired LoD2 building models in the 3DShape format (Polygon ZM). This LoD2 data needs to be prepared for a R-script of solar irradiation calculations on roof surfaces, but which can only ...
3
votes
3answers
768 views

Determining the area of each polygon within a polygon boundary?

I have a series of maps representing a 1000m diameter around a point. These maps contain 40 different types of polygons that represent a land use (ex. Corn crop, Pasture). I want to select all ...
3
votes
1answer
89 views

Showing multiple burials in same grave for Cemetery GIS?

I am an intern creating a Geodatabase for a municipal cemetery. The one lot can hold up to 3 people (2 people, 1 cremation) two people at the most. How would I show that information on the map ...
0
votes
2answers
98 views

Java library for polygons interesection

I have an Android app when I have multiple polygons of a person's position, and I want the intersection of these polygon to know his exact position.
1
vote
2answers
106 views

How to create a polygon grid with un-even spacing between research plots?

I have an orthomosaic of a crop field with small research plots (3.8 X 1.44 m and 0.22m b/w plots and 0.50m b/w range spacing). I would like to create a polygon layer using this information. After ...
1
vote
2answers
194 views

Maximum distance to polygon edge

I have a point feature class and a polygon feature class, and each point is located within one polygon. Is there a way to programmatically calculate the distance from each point to the farthest ...
1
vote
1answer
55 views

sorting polygons extracted using Fishnet

I generated polygons using fishnet in ArcMap, since the polygons didn't fall exactly on top of my raster image, I had to edit and move some of them. Now the FID of my polygons are all messed up, and ...
1
vote
1answer
304 views

Remove lines from inside a polygon in QGIS

Through a "dissolve" process in QGIS, I achieved some polygons that have some fails, like this one in the screeshot: Is there any automatic process I can make in QGIS to remove those lines inside ...
1
vote
1answer
78 views

Edit raster classification manually using polygons - ArcMap

I want to edit the elevation/z values of certain zones on a raster in ArcMap. I followed this example by creating a polygon, assigning a value of 7.5, then converting the polygon to a raster, finally ...
1
vote
1answer
200 views

Assign overlapping polygons based on attribute

I am using ArcGIS 10.1 and have a polygon shapefile with 16000 records. There are many polygons that are overlapping and my goal is to determine the overlap portions fix the problem, so that there ...
2
votes
1answer
657 views

Is it possible to have self intersecting polygons in shapefile?

GIS vector data for example shapefile contains polygonal data. Lets assume, we have polygon A which has self-intersection which means that the edges in this polygon intersect with each other. Lets ...
1
vote
1answer
82 views

In PostGIS: How to delete completely overlapping polygons?

I would like to eliminate overlapping polygons from a table that is often updated with new polygons, but only if a certain attribute has a higher value. If this higher-priority polygon only partly ...
1
vote
1answer
146 views

FeatureToPolygon (to cut polygons by line) not working correctly outside of ArcGIS

I asked a question yesterday, about splitting polygons using a line, and I ended up using the approach that is described in the comments here. Although this worked with my test data, it causes a lot ...
1
vote
0answers
27 views
1
vote
2answers
427 views

How to make a circular polygon in QGIS?

I am trying to make a floor plan for my office, have managed to make all of the rectangular components (e.g. the rooms) however some of the desk layouts are circular and I haven't been able to work ...
16
votes
8answers
34k views

Extracting coordinates of polygon vertices in ArcMap?

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 ...
6
votes
3answers
4k views

Creating square grid polygon shapefile with Python?

I have the following coordinates minx, maxx, miny ,maxy = 448262.080078, 450360.750122, 6262492.020081, 6262938.950073 I wish to create a square grid of size 1 m using python. import math minx,...
2
votes
1answer
648 views

Optimizing ArcPy code to cut polygon?

There is a lot of nested loops and wondering of ways I could speed up this code? Any ideas? Note: This requires ArcMap 10.2 def cut_geometry(to_cut, cutter): """ Cut a feature by a line, ...
4
votes
2answers
402 views

Dissolving/Unifying Ill Behaved/Irregular Polygons in R

I'm working on a project involving bringing together multiple subjects circling difficult to find parts of an image. The output from users is pretty awesome. Cool, right? However, what I want is ...
0
votes
1answer
163 views

Adding pixel value data from a raster layer to a number of buffer polygons ArcGIS

I have created a layer of polygons with buffers around my points of interest, all of the same size, in Arc GIS. I also have a raster layer of nighttime lights with pixel values between 0 and 63 ...
5
votes
1answer
748 views

Create raster with grid cells values based on area covered by polygons

I have a polygon data with area covered by the forests (data is here - https://www.dropbox.com/s/zgckliydalljw6a/sp_data.zip?dl=0). I want to convert polygons to raster. The value of each grid cell ...
3
votes
1answer
472 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
184 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 = feat.geometry().asPoygon()...
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
89 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 ...