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
votes
2answers
165 views

how can we save vector layer as a file in openlayers

Im using mapserver + openlayer for GIS API and im new to GIS. I'm done with drawing line, point and polygon features in openlayer. but not being able to save it in some shapefile afterwards i got to ...
3
votes
0answers
54 views

Merge n number of adjacent polygons

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 ...
1
vote
1answer
82 views

Average width of irregular polygons QGIS 2.12.0 Lyon

I'm interested in examining the average width of streets, that are irregular polygons, for a project. I'm using QGIS 2.12.0 Lyon, and have lines (power cables) and Polygons (streets) as layers. For ...
0
votes
2answers
34 views

Polygon Torque Map- problem changing polygons to points

I'm trying to alter my data on cartodb map to get maritime emissions over about 20 years- by country. Hence trying get a torque map for polygons, and by changing polygons to points based on a ...
4
votes
1answer
62 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 ...
3
votes
1answer
62 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 ...
2
votes
0answers
9 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
37 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 ...
11
votes
3answers
12k views

Converting Polygon into single or all Points using QGIS?

I want to convert polygons into points using QGIS. I know how it's done in ArcGIS Desktop.
6
votes
0answers
40 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
29 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 ...
5
votes
1answer
60 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 ...
5
votes
2answers
69 views

Identifying a cluster of polygons based on attributes

I'm trying to identify a cluster of contiguous parcels that, when combined, add up to at least a given size and, when combined, have an assessed property value less than a given $ amount. I have a ...
0
votes
1answer
20 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 ...
3
votes
4answers
2k views

How to remove vertices or lines within a polygon?

I have transformed a *.dxf-file into a polygon shape-file. In many of the polygons i have lines whicht do not belong there but i can not delete them as i normally delete vertices on polygons by ...
1
vote
0answers
37 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 ...
0
votes
1answer
232 views

Clip multipatch to polygon ArcToolBox

I have a multipatch dataset and a 2d polygon. Which ESRI tool can I use to select only those multipatches whoms x,y are inside the polygon? Basically I want to select all multipatch features that ...
1
vote
1answer
182 views

Extruding a 3D stack of polygons on top of a map, e.g. with KML

I have data for the composition of rock layers in several polygons on earth. I would like to plot a stacked chart of the rock layers, colored based on layer metadata. Here's a mockup, where rock ...
3
votes
1answer
5k views

Exporting query to identify what polygon certain points fall in using ArcGIS Desktop?

I'm using ArcGIS Desktop 10. I have shapefiles consisting of points (street addresses). I also have shapefiles consisting of polygons (ie, congressional districts, city council districts, etc... a ...
3
votes
2answers
808 views

How to do a Point to Polygon analysis with multiple variables in QGIS?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...
2
votes
1answer
311 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 ...
1
vote
1answer
38 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
11 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> ...
0
votes
3answers
2k 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 ...
2
votes
2answers
36 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
2answers
412 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 ...
1
vote
0answers
42 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
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 ...
1
vote
2answers
193 views

Intersection point of polygon and the line created by two points ArcPy

I have polygon layer. I selected the most distant vertex from centroid (picture: point A). (How to do that is in the answer here: Select the most distant vertex from polygon's centroid using ...
2
votes
1answer
36 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. ...
9
votes
1answer
1k views

Fixing orphaned holes in R

I'm trying to perform a union on a common field after merging two adjacent shapefiles. The shapefiles end up with at least one thin sliver of space between them. When I attempt a union I get the ...
3
votes
1answer
37 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 ...
1
vote
2answers
179 views

Split polygon based on line segment

I am trying to split a street polygon based on the segment ID of the street, giving them the same segment_ID in the attribute table of the street lines. I did not use the line feature class to derive ...
12
votes
9answers
26k 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 ...
4
votes
3answers
578 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
vote
2answers
48 views

Labeling each side of polygon with its length in ArcGIS Pro?

I am trying to figure out a way in ArcGIS Pro to label each side of a polygon with the length of the side without breaking it into individual polylines.
0
votes
1answer
181 views

Using ArcGIS Tabulate Intersection to determine maximum land cover within polygon area

I have a shape file (layer A) containing different polygons - each polygon representing an ecoregion. I have another layer of polygons (layer B) - each polygon representing a watershed boundary. I ...
0
votes
2answers
924 views

How to export to all points within Leaflet polygon?

Is it possible to export all points within a polygon drawn using Leaflet? (http://leaflet.github.io/Leaflet.draw/).
1
vote
1answer
370 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, ...
0
votes
0answers
20 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 ...
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 ...
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 ...
3
votes
1answer
41 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
38 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 * ...
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 ...
2
votes
2answers
127 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 ...
5
votes
2answers
2k views

r - increase speed of crop, mask, & extract raster by many polygons

I'm extracting the area and percent cover of different land use types from a raster based on several thousand polygon boundaries. I've found that the extract function works much faster if I iterate ...
1
vote
2answers
33 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: ...
1
vote
1answer
30 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 ...