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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2
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1answer
14 views

Google Earth Polygon surface area to follow the curvature of the earth model

Question: When drawing a polygon in Google Earth with latitude, longitude and elevation values at each node, how do you ensure that the surface area of the polygon also represents the desired ...
0
votes
2answers
21 views

How to calculate area in sq m - troubleshooting projection issues in a global dataset in QGIS

I am using QGIS version 2.12.3. I have 3 polygon shapefiles: A, B and the intersect of A and B, which we can call C. All I want is to add a field to the attributes table of each shapefile giving ...
3
votes
1answer
40 views

How to create a fishnet/grid along a polyline or polygon

I am trying to generate a fishnet/grid along a line/polyline or polygon boundary in ArcGis 10.3 or QGIS. While it is totally intuitive and easy to generate a box-standard grid, what I am trying to do ...
2
votes
1answer
27 views

Converting Shapely MultiPolygon to Polygon: Technique doesn't always work

In order to get the exterior coordinates I need to convert a shapely MultiPolygon to a Polygon. I do it like this: if poly.geometry.type == 'Polygon': x, y = poly.geometry.exterior.xy elif ...
1
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0answers
42 views

Grouping polygons by spatial attributes

I'm working with a dataset that contains millions of polygons representing leased properties. In many cases, there are multiple polygons that are drawn on top of one another (representing multiple ...
0
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2answers
41 views

Dividing an irregular polygon into sub-regions

I am trying to divide an irregular polygon into equal widths and am having trouble understanding the proper tool to use. I am in possession of ArcGIS and am aware that the Parcel Editor is the closest ...
0
votes
0answers
37 views

What is a polygon, a ring, a part in arcpy, ArcMap-editor for the OGC and in GIS generally

I ran in some difficulties to the definition of the term polygon as i tried to understand arcpy's geometry model. (ArcPy getPartCount always returns 1 on multipart polygons?) I ended up in consulting ...
0
votes
1answer
32 views

How to select congruent polygons in PostGIS?

Title says it all. What is the best way to select congruent polygons in PostGIS? CREATE TABLE polygon_a ( gid serial NOT NULL, geom geometry(Polygon, your_SRID), CONSTRAINT polygon_a_pkey PRIMARY KEY ...
2
votes
0answers
91 views

Merge n number of adjacent polygons [on hold]

I have over 17,000 individual polygons. I want to merge two adjacent polygons so that I finish with approximately 8,500 polygons. The polygons need to be merged based on location, merge two adjacent ...
2
votes
0answers
11 views

Geocode area/neigborhood into polygon vertices

I have been successfully using the Google Maps API using the R package ggmap to find location coordinates for e.g. addresses or city names. However, Google Maps now shows areas as well, indicating ...
2
votes
1answer
39 views

Polygon data to Point Feature Data

Using ArcGis 10.0. What I am looking for is a way to get point features that are placed in a polygon to have the same "Address" value. This is the same as the "Spatial Join" feature, however, I am ...
6
votes
0answers
63 views

Project an attribute from one polygon layer to another

I have 2 polygon layers which can be found here. The two layers are overlapping. The first contains a map of the German counties in 1928 and the second the counties how they are in 2014. The 2014 ...
4
votes
1answer
32 views

Edit polygon borders in QGIS preserving topological correctness (planar partition)

Given a layer of polygons that is topologically perfect, i.e., has no overlaps or gaps between the polygons, is it possible to manually edit the edges of the polygons in QGIS in a way that preserves ...
4
votes
1answer
67 views

Find all intersections of a LineString and a Polygon and the order in which it intersects it

I would like to find out all intersections of a LineString (River) through Polygons (Municipalities). I would like to list the order of municipalities which the river crosses, using linear ...
0
votes
1answer
21 views

Hatching over simple fill in ArcGIS 10.3

I have a polygon layer that is symbolized into four categories. Two of these categories are above a threshold limit and two are below. I would like to further distinguish the two categories above the ...
5
votes
1answer
62 views

Aggregating polygons with space between them

Im currently editing a large dataset that has large chunks removed throughout (buffered road network). The areas adjacent from each side have coinciding attributes, but have this large erased area in ...
1
vote
1answer
41 views

Merge polygons in the same shape file based on attributes, ArcGIS or ArcPy

I have a shapefile of polygons. I do not want any polygons with an area less than 25. For polygons with an area less than 25 I want to merge them with another polygon with an area greater than 25 that ...
0
votes
0answers
12 views

Intersect Iso_rectangle_2 with Polygon_2 where Polygon_2 uses Projection_traits_xy_3

I have a set of [Point_3][2] that constitute a Polygon_2 using the Projection_traits_xy_3 typedef CGAL::Exact_predicates_inexact_constructions_kernel K; typedef CGAL::Projection_traits_xy_3<K> ...
1
vote
0answers
45 views

Calculating area of intersection of polygon to another layer in ArcGIS for Desktop?

I am very new to GIS, especially ArcGIS. I am currently using ArcGIS 10.2, and I have 2 layer, namely the purple feature map(this layer is an import from arcgis online, it doesn't seems to be an ...
1
vote
0answers
39 views

Spplot SpatialPolygonDataFrame and SpatialGridDataFrame

I have to plot in the same graph something like this: Then, I have elements from SpatialPolygonDataFrame class and others elements from SpatialGridDataFrame class. When I try to plot them in the ...
2
votes
2answers
42 views

Use function spplot

Does anybody know how to plot with "spplot" fuction two elements of diferents classes?. One element from "SpatialPolygonDataFrame" class and other from "raster" class.
1
vote
0answers
29 views

Selecting certain area of polygon according to size in ArcMap?

I have a set of polygons with a certain size (3500 sq meters each for examples). I only need 3000 sq meters of every polygon. Is there an automatic or semi-automatic way to create sub-polygons out of ...
2
votes
1answer
37 views

Creating polygon regions with latitude and longitude values in qgis?

I've a set of places with their latitudes and longitudes, I've plotted them on QGIS but what I want is to create polygon from these points so that each point refers to a particular region around it. ...
3
votes
1answer
39 views

ArcGIS find all polygons that intersect with more that one polygon from another layer

I have two layers with polygons. I want to find those polygons from first layer that intersect with more that 1 polygon from second layer and find those intersected polygons ID numbers: 1 from first ...
0
votes
0answers
22 views

How to calculate the number of markers with in a polygon in openlayers3

I am using https://github.com/tombatossals/angular-openlayers-directive openlayers angular repository and plotting markers on the map as shown below <!DOCTYPE html> <html ...
0
votes
1answer
24 views

Masking low quality raster with polygons in R gives weird overhang?

I am pretty new to R, and have been attempting to use the mask function on a raster image of 250mx250m resolution. My problem is that for some reason I am getting overhang, as there are pixels which ...
1
vote
0answers
23 views

Polygon to Raster tool while keeping less than maximum values

I'm trying to convert a very large, detailed polygon to a raster with a coarser resolution in ArcGIS 10.1 using the polygon to raster tool. The value field is a percentage and the cellsize must be the ...
1
vote
2answers
49 views

Grouping polygons and other geometrical shapes

My situation: I have administrative areas marked with polygons Many areas have many, many, many islands I need main area and all it's islands to change color when any of the islands or main is ...
3
votes
1answer
42 views

Find out if overlaying polyline matches polygon centerline in qgis

I have a polygon and a polyline and I need to find a scientific way of how close that polyline is to the actual polygon centerline. Is there any way of doing this in qgis? Any extensions, models, ...
1
vote
2answers
39 views

How to combine two polyline shapefile together

Here is my question Two shapefile: * A: represent the outer boundary of the city area * B: represent the inner boundaries of the city divisions. I want to * Combine these two shapefile * ...
3
votes
1answer
63 views

Counting polygons in one layer that are overlapping/touching/contained in each polygon in separate layer of contiguous polygons using QGIS?

I have a layer of contiguous (pink) polygons (UK Parliamentary constitutencies) and a separate layer containing (blue) polygons representing protected nature areas (Natura 2000 areas): Each ...
1
vote
1answer
39 views

Decompose the polygon with polyline inside

Here is my question: I have a polygon shapefile represent the whole country area. A polyline shapefile(with a bunch of line boundaries) represent the province boundaries So, how to decompose the ...
1
vote
1answer
31 views

extracting statistics from a raster within the extent of a polygon

I have a polygon representing the extent of a study area. This polygon is overlaid to a raster representing the quality of land, which is classified into 5 classes (from bad [1] to good [5]). I would ...
1
vote
2answers
36 views

How to compute the distance from the current polygon centroid to another in QGIS field calculator?

There is layer with polygons. I want to save in new field distance of every polygon's centroid to centroid of one particular polygon. To do this I should write some expression like this: ...
2
votes
0answers
24 views

Intersect, Spatial Join?: One Line crossing Multiple Polygons, assigned wrong attribute

I am looking for any possible solutions to a problem I am encountering with ArcGIS. I am using census block groups (CBG) to assign streets an income level value based on their location within the ...
4
votes
1answer
42 views

How to find 2nd order polygon neighbors? (and 3rd, 4th etc.)

I have a shapefile of contiguous polygons and for each pair of polygons, I need to know how many polygons are between them, following an neighboring/bordering approach. The output is likely to be a ...
2
votes
0answers
25 views

Adding attribute data together within multiple polygons in QGIS? [duplicate]

In QGIS I have two vector layers, the first is a set of polygons and the second is a series of points. Each point has a numerical attribute associated with it and is located within one of the ...
2
votes
1answer
48 views

Tutorial to create Shapefile based on Districts using ArcGIS for Desktop?

I have been tasked to create shapefile of Amritsar, India (will be incorporated into R programming language) So far, I see this 2-part video tutorial, where person is assigning numbers and icons, ...
4
votes
2answers
118 views

Clip polygon using buffer

I'm very new to QGIS, so apologies if this is a daft question. I've been trying to resolve my problem for a couple of days and I can't get anywhere. I have searched for similar issues here on SE but ...
2
votes
1answer
50 views

Selecting features of vector layers based on another vector layer using QGIS?

I am using QGIS 2.12.2. I am using three vector layers (point, polyline and polygon shapefiles) of the region of interest. Any advice in making the selections from one dataset based on the other ...
0
votes
0answers
30 views

How to not display a layer, if its below a other semi transparent layer?

I have two polygon layers (PostGIS). One of them is semi transparent. If the other layer is below the semi-transparent one, it should not be displayed. My situation at the moment is: The grey ...
4
votes
1answer
54 views

Remove sliver gaps between polygons with R

Is there a way to eliminate the small "slivers" between polygons using R? The desired solution would create a new SpatialPolygonsDataFrame where the shared boundaries between polygons are coincident. ...
6
votes
3answers
78 views

Select all polygons that are completely within a circular buffer

I made several buffers around some points. Now I want to select all polygons that are completely within this buffer. My problem is that I also get the polygons that are partially outside of the ...
0
votes
2answers
88 views

Adding one search box for multiple GeoJSON polygon layers?

Multiple GeoJSON markers can be combined to one group layer then search on a specific attribute but doesn't work for GeoJSON polygons. How to put multiple GeoJSON markers and polygons in one search ...
0
votes
0answers
29 views

How to bind event to Polygon inside polygon in google maps.?

I am drawing a polygon buffer in google maps api v3 and finding number of polygon objects lying inside it.(on click) I am using oracle spatial database. on each child polygon click i need to do some ...
2
votes
1answer
52 views

How to rasterize an object of class SpatialPolygonsDataframe in R

When I read a polygon shapefile into R using rgdal, it was imported as an object of class SpatialPolygonsDataframe. I need to rasterize the polygon, but the rasterize{raster} function requires it to ...
4
votes
0answers
40 views

Buffer neighbouring polygons without overlap using QGIS

Is it possible to create a buffer around neighbouring polygons, so that the new polygons do not overlap? Preferably in QGIS but any other tool will do. So instead of the first result I would like ...
2
votes
1answer
56 views

Trouble adding proportional circles on top of symbolized polygon in ggplot2 map

Data: Zipped ea.ml1 shapefile can be found here, and the country outline can be downloaded here at the GADM site. I've been using the Ethiopia ESRI shapefile. Branch locations are here. Per the ...
1
vote
1answer
42 views

How to create custom discrete color scheme for polygon attributes in ggplot2?

Back again with more questions. :) Data: Zipped ea.ml1 shapefile can be found here, and the country outline can be downloaded here at the GADM site. I've been using the Ethiopia ESRI shapefile. As ...
2
votes
2answers
37 views

How to calculate the intersection within the grid and saving to the grid

Here is my example: (1) I creat the grid line layer using MMQGIS plugin (2) I use line intersection function to get the intersection points. I want to calculate the distance sum within each ...