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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4
votes
2answers
57 views

Display multiple identical polygons (with different attributes) on map

I need to create maps of multiple species in a certain area. However sometimes multiple species occurr in the exact same area. This results in two identical polygons on top of each other. Many of ...
0
votes
1answer
210 views

Converting polyline data to polygons?

I am trying to convert some polyline coastline data into a polygon that I can use to clip/subset back other data sets by this polygon. There are some small gaps in the coastline data, which ...
1
vote
0answers
20 views

ol3-cesium polygon float

I’m trying to build a webmap using ol3-cesium libraries , when I switch 2d map to 3d map my polygons (geojson or geoserver wms, wfs) are not draped on stk-terrain but they are under the ground. I ...
2
votes
0answers
158 views

QGIS, How to label a layer in different font sizes, shrink to fit in polygon or a multiple line label?

I am just trying to figure out how to label a polygon layer to fit its size in QGIS. or if its very long title should break in line and scale, i did some research but couldn't find anything helpful is ...
2
votes
2answers
181 views

How to quickly fill multiple gaps in a series of adjacent polygons

I've been given a "background" dataset which is designed to draw as the first layer in a complicated map. For some reason the data provider has previously erased this dataset with roads, parks, etc. ...
0
votes
0answers
24 views

R - `rasterize` of polygon fails to properly take account of internal hole

I'm trying to use R to mask out a DEM raster using a polygon (loaded from a GML shape file) using the following code, where dem_modern is the raster and modern_land_shape is the vector polygon : # ...
0
votes
1answer
24 views

How do I make a grid around all my points, and then convert it to a polygon [duplicate]

I want to make a grid around all my points, convert to a polygon and use this to clip the extent of my data. I am using Arc 10.2. How do I make a grid and then convert it to a polygon? Or is there a ...
0
votes
2answers
157 views

Intersection between line and polygon

I have 2 layers in OpenLayers: first is parcel layer (polygons) and second is railway layer (lines). They are already drawn and all I need to do is when I click on some line, to get intersection of ...
0
votes
1answer
336 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 ...
3
votes
1answer
491 views

Determine when I have crossed state line?

We are currently using the Google Maps API to get route information and total mileage but we would like to determine when we are crossing into a new state. When we return the route information we can ...
0
votes
2answers
41 views

How to (precisely) re-align a polygon

I have this shapefile and I want to re-align the selected polygon (See image below) to the shapes of the other polygons. I tried using the "edit tool" but it's not producing a good result. What would ...
3
votes
1answer
27 views

Problems with dividing multipolygons into polygons

I have a shapefile with countries boundaries downloaded from here and I am trying to upload it to PostGIS database with ogr2ogr. This file contains features of polygon and multipolygon types and ...
3
votes
1answer
48 views

Create an optimised path between nodes avoiding polygons entities

I have a point shapefile representing seaports. I have the linear cost of shipping for every seaport pairing (specific shipping cost to go from one point to another point). I want to find a way of ...
4
votes
2answers
62 views

How to Select a Polygon beneath another Polygon in QGIS 2.14

We have a series of layers that contain polygons with additional polygons 'underneath' each polygon. How do we select the polygon beneath the existing feature without also selecting the feature ...
1
vote
1answer
30 views

“Hole” argument ignored in call to Polygon function

I am working with a dataset consisting of a list of coordinates for a set of polygons. Some of these polygons are holes. However, the dataset does not follow the convention of listing the coordinates ...
1
vote
2answers
284 views

how to find that two polygon boundaries are connected?

I am working on a Geo database where there is a layer with many polygons. i want to find that which polygons boundaries are connected so that i can create new layer from that polygons and which ...
1
vote
0answers
19 views

Looking for Polygon data on NUTS2 (2013 system) in CSV or Excel?

Looking for Polygon data on NUTS2 (2013 system). Can somebody supply this in CSV or Excel? I have been searching on NUTS2 Polygon data, but unlucky so far. I have found the data but this is in ...
0
votes
0answers
29 views

Generate points layer at line intersection

I have a line layer that is actually buffer polygons converted to a line layer. I would like to generate points at all places where 3 or more lines intersect. I would settle for places where 2 or more ...
0
votes
0answers
23 views

Drawing line and finding bearing using ArcGIS for Desktop?

I need to draw a line from a point within a polygon to the edge of said polygon. I do not need to know the length of the line, only the bearing (in degrees) for the line. We are using ArcMap 10.3.1
3
votes
1answer
823 views

Extract data from netcdf using a shapefile polygon in python

I need to subset data from a NetCDF using a specific shapefile. The data are sea surface temperature and ocean color at 1/4 degree resolution. I have 4 polygons describing the US. Northeast ...
0
votes
0answers
72 views

Polylines and polygons - QGIS-2.14.3-1

After extracting contour lines from a DEM (obtaining polylines), and transforming them to polygons, I export the vector layer with polygons to a DXF. Then I import the DXF into Corel Draw to manage ...
5
votes
3answers
158 views

Smoothing method for big polygons

I'm looking for an alternative to 'snakes method' for smoothing very big polygons, which I created from SRTM elevation datasets. The problem is that the smoothing is getting stuck after a while with ...
3
votes
2answers
125 views

Creating OUTSIDE_ONLY buffer around polygon using R?

I would like to create buffers in polygons, surrounding my original polygon. However, I want to keep only the "outside polygon", not include also original polygon. In Buffer in ArcGIS I can just set ...
3
votes
3answers
1k views

How to filter out multipart polygons and then buffer?

I've written a small script trying to accomplish the task described in the question title. It basically looks like: in_fc = '...' # Some shapefile goes here # Get the fields (column names) of the ...
0
votes
1answer
184 views

Looking for specific polygon boundaries of DMA regions

I am trying to create a map in CartoDB and I need 2 specific polygons for it. The regions are: DMA_id, DMA_Name 743 Anchorage, AK 744 Honolulu, HI I searched every source I have and those two are ...
1
vote
1answer
45 views

Colour specific polygons on a postcode map - QGIS

I am working on a UK postcode map. It only has the first bit of the postcode, e.g. BR12. I have an excel spreadsheet with the longitude/latitude of specific points as well as their postcodes. Instead ...
4
votes
1answer
2k views

Create overlapping polygons from contour lines

Working in ArcGIS 10, I have a set of contour lines representing density of commercial square footage, and I have a set of points representing local maxima for each peak of the dataset. For each ...
1
vote
1answer
32 views

Combining Data from raster and polygon

I am teaching myself GIS at the moment, and there are still some matters I haven't quite got the hang of. I'm using ArcGIS 10.1, and have three datasets: LAYER 1: A population dataset at a high ...
3
votes
0answers
48 views

Emulating Polygon Neighbors tool in ArcGIS Desktop 10.0? [duplicate]

I'm using ArcGIS 10.0 SP5. Have a set of 4000 polygons (featureclass A) and I'd like to summarise the values of the polygons (featureclass B) which touch the boundaries of these polygons (ie. those ...
1
vote
1answer
38 views

Splitting polygon into multiple fixed-width polygons along edge in R?

I have a polygon and would like to spit into grid with fixed width along with one edge. The result will look like the figure below. Are there algorithm to achieve my target? My language is R, but ...
0
votes
1answer
41 views

ST_Union or ST_Collect on PostgreSQL union result?

Newbie to PostGIS/Postgres. I have the follow query which returns me 2 GEOMETRYCOLLECTIONS. Is there a way within my current query to return one polygon? SELECT ST_AsText(ST_Collect(ST_Simplify(geom,....
10
votes
2answers
12k views

Converting point sets to polygon boundaries?

I'm trying to convert sets of points to their respective polygon boundaries. I think this is something like a Voronoi diagram or Convex Hull, but not quite. I'm sure there's a technical term for it, ...
7
votes
2answers
155 views

How to calculate how many polygons I can put inside a polygon?

I usually use qgis. I explain my problem with an example: there is a forest (irregular geometry1 ) and one tree (geomery2). I want to know the maximum number of trees that the forest can contain. ...
1
vote
0answers
26 views

QGIS - convert multiple polygons to evenly spaced points within polygon boundary

I need to convert the polygons in a vector layer to evenly spaced points within the polygon boundaries in QGIS. The vector file contains >1000 polygons mostly with overlaps. The attribute data of ...
1
vote
2answers
63 views

Calculating relative share of area covered by water/percentage of polygon area that overlaps in ArcGIS for Desktop?

I need to calculate the share of the area within a 50km radius of major German city centers that is covered by water with either Arcmap 10.3.1 or Qgis 2.14. My plan is to use the Global Lakes and ...
1
vote
0answers
53 views

Creating voronoi polygons from polygons?

I have a database with buildings and for some further analysis I need to: aggregate adjacent buildings (preferably without losing the height attribute, but I can work my way around that) once I have ...
0
votes
0answers
57 views

How can I fix Russian border polygon?

is there easy way to fix Russian border polygon in CartoDB? The polygon is given by CartoDB. From the picture you can see that the polygon covers also Estonian territory. But I need to make there (on ...
1
vote
0answers
38 views

Algorithm to simplify a Polygon/Series of Points to a given number of Points

I have a polygon (or let's call it just a series of points). I want to simplify it (reduce the amount of points) to a given number of points. Currently I use Douglas Peucker and try to guess the ...
1
vote
1answer
36 views

QGIS 2.81. Why can i only see my whole polygon and nothing if i zoom in

I have a polygon layer with one object. It is a flood inundation map. I could see my layer all the time in every scale factor. From one moment to the other it changed and know it is only visible if i ...
3
votes
1answer
63 views

How can I merge two adjacent polygons which borders are not touching each other

I want to merge adjacent single polygons which are apart from each other. Important note: I cannot use ArcGIS, I need to do this programatically, in any language (R, Python, Ruby, PostGIS) doesn't ...
1
vote
2answers
60 views

How can I build a grid of equal square polygons in ArcGIS 10?

Not having them depend on decimal degrees, but on a certain distance. When I use a tool it asks me the length of the cell in degrees, but I want all sides of every cell to be equal and with degrees ...
1
vote
0answers
18 views

QGIS-I have 37 polygons, can I bulk create 2 other sets of 37 that are 1 px larger all the way round and 1px smaller

I have 37 polygons covering a Lakes spatial extent at a particular point in time. I need to bulk create 2 sets of polygons. One 1 px larger all the way around and one 1px smaller to calculate the area ...
1
vote
1answer
26 views

How to auto Correct Polygons that are not drawn correctly?

I was part of a project recently where handheld GPSs were used to collect vertices of parcels. After plotting the points using 'P2One' plugin in QGIS I found out that some of the polygons were twisted ...
3
votes
1answer
62 views

Rule based polygon fill in QGIS?

I'm really quite new to QGIS, I want to style polygons fill with raster imagws based on a attribute contained in the property table. What do I have to write in the description in order to get for ...
3
votes
0answers
48 views

Find Distance Between Two Polygons

Given two polygons (point, line, or up to 8 vertices) I need to be able to calculate the shortest distance between them via code I write or a call to an API (I haven't been able to find one that does ...
0
votes
1answer
61 views

Inverted lat lon on drawn polygons in Openlayers 3

I am working on a map in openlayers 3 with geoserver I display the layers as WFS and I added the draw and modify interactions, but when I save the drawn polygons the coordinates of the newly drawn ...
0
votes
0answers
10 views

Allocating premises between postcode polygons and telephone exchange area polygons in QGIS?

I have telephone exchange areas as one polygon layer and postcode (codepoint) polygons as another. The postcode polygons have the number of premises in each postcode as a field. I want to estimate the ...
0
votes
0answers
10 views

MSL/AGL bounds checking in PostGIS for Line/Polygon Intersection

I have a table with Polygons and columns defining an optional upper and lower altitudes bounds and altitude type. The Type can be MSL, AGL, or NULL, if unbounded, and can be set separately for upper ...
1
vote
0answers
20 views

scale polygon in Qgis [duplicate]

The task is to scale a polygon in QGIS. The procedure is performed tracing the polygon and then apply a scaling factor ( the factor used is " Distance on the ground" / " Distance on map " ) . Both ...
1
vote
0answers
23 views

SRIDs do not match for the two geometries in oracle spatial

I am trying to resolve where some points from Point Geometry lying outside the Polygon geometry. I want to filter those points which are lying outside the polygon geometry. I am getting error where ...