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
1answer
512 views

How do I smooth edges of polygons in QGIS?

Is there a built in function or plugin I can use to achieve smooth lines for my polygons instead of the blocky ones I have now?
-1
votes
0answers
24 views

Trying to join a column from one table to another using python [duplicate]

So I have two tables, one has county polygons, the other has well Points. I am trying to first calculate the total numbers of wells that fall into that county, and update the county table with the ...
2
votes
2answers
392 views

How to create a polygon fill as seen in the QGIS 2.16.0 changelog?

The polygon fill for 'Urban parcels' in the following .gif animation looks really cool. http://changelog.qgis.org/media/images/entries/5817785cf3d18db78669c2eb2c2be0cf606c3783.gif (See also: http://...
0
votes
1answer
370 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 ...
2
votes
2answers
186 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. ...
1
vote
1answer
86 views

Edit raster classification manually using polygons in 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 ...
0
votes
0answers
12 views

How to render elevation polygons as concentric polygons with increasing order of their height at given point in geoservert

I have create a postgres database that contains the elevation polygons at various elevation heights of sachsen. I wish to render these elevation polygons in a similar manner as they appear in the open ...
32
votes
10answers
33k views

Removing small spaces (slivers) between polygons?

I have a set of polygons representing administrative districts. The districts were digitized by hand, and there are small spaces (slivers) between polygons where the polygons should be touching. How ...
0
votes
1answer
1k views

How to narrow the result from Nominatim with only cities and countries, no additional areas with the same name?

I'm trying to get WKT or GeoJson polygons of cities and countries from Nominatim (for example, Paris and France). I send a GET request but it returns me several results named "Paris" or "France". How ...
2
votes
0answers
29 views

Python Shapely - filling small gaps between multi polygons

I have a set of rectangular polygons, which currently form a directional path. The library I am using is Python Shapely / GeoPandas. The issue I am having is as the path changes direction, there are ...
5
votes
2answers
91 views

Perfect circle in ArcGIS, why I get a multiside polygone (plurigone)?

Using ArcGIS basic (10.3), I tried to make perfect circles in ArcGIS with the buffer tool. As you can see on the two print screens, the circle is not perfect when I use a radius of 7,5 meters in a MTM ...
0
votes
0answers
39 views

Raster to polygon tool not working

I am trying to convert a raster to polygon in ArcGIS 10.2.2 but when I run the tool, it says complete but no polygon file is created and the tool window pops up again. I have tried converting the ...
0
votes
1answer
43 views

Convert SpatialPolygonsDF boundaries to SpatialLinesDF keeping information on polygons

I have a SpatialPolygonsDataFrame and I need to convert polygon boundaries into a SpatialLinesDataFrame retaining the attributes of the 2 polygons The structure of the SPDF looks like this 'data....
0
votes
0answers
46 views

Select Markers Via a polygon and get the name

I created a map with open layers where i am able to select Markers, make them names appear in a field. But now here is my problem : i want to be able to select markers with a polygon, draw my polygon ...
0
votes
0answers
36 views

find a percentage of an irregular polygon area like a county

I need to find a certain percentage (69%) of the area of an irregular polygon. Not a parcel. I am using ArcGIS 10.3.1 Desktop.
1
vote
1answer
43 views

How to split polygon into equal segments in QGIS?

I try to split polygon layer into equal length segments of 1000m: The attribute table of the layer is: I have read those links but didn't find a solution to my question: How to split a vector ...
0
votes
1answer
30 views

Quick way to produce polygons to cover variable precision lat / lon points?

I'm using the Smithsonian Global Volcanism Database and have a .csv lat lon points from it. It seems they are using decimal precision on their lat lon to give a rough idea of the size of the area that ...
1
vote
1answer
33 views

Measure polyline length in QGIS

I try to measure the length (in meters) of the polyline layer that pass inside the olive polygon layer only, and if it possible export the wanted polyline into new layer: the attribute table of the ...
0
votes
0answers
20 views

Openlayers 3 polygon not rendering on map

I've set up a small example of an OpenLayers 3 map, and I am trying to add a custom polygon to the map. If I use the data from the example, it works correctly, the polygon renders, and it is shown on ...
1
vote
0answers
24 views

Changing colors in SVG file polygon using QGIS?

I try to change colors and lines width in this polygon (this is SVG file): I learn from here SVG symbol colors differences in QGIS 2.12? Using SVG file to fill polygon using QGIS- problem to add ...
0
votes
0answers
56 views

Which GIS software allows manually creating shapes from overlapping shapes of other layers?

I have two shapefiles, one showing the borders of the US states, the other one showing river basins. Both layers are filled with solid colors, with the US states differing in hue and the river basins ...
5
votes
1answer
206 views

Generating surfaces of different heights from LIDAR points

I am seeking a way to generate surfaces (polygons in a 3D space) of different heights from LIDAR point clouds, whose spacing is 4 points per square meter. The typical application is like roofs, which ...
3
votes
1answer
510 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 ...
3
votes
1answer
964 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
5answers
2k views

Fix Self Intersecting Polygons Manually [closed]

I are looking to implement a method to fix self-intersecting polygons by editing the vertex order. We want to take the polygon rings and re-arrange/add in vertices to make a valid polygon. This is ...
2
votes
1answer
289 views

R Spatial: Trouble with disjointed polygon that has self-intersections

I have a shapefile which represents the areas of a city which have higher risks of flooding than others. This is a spatial polygon object however the polygon is disjoint and not connected. I also have ...
0
votes
1answer
199 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 ...
4
votes
3answers
938 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 ...
0
votes
0answers
9 views

Values missing with Polygon to Raster tool

I am trying to convert a polygon to raster using a field with six unique values as the 'Value' field in ArcGIS 10.2. However, when I do this, one of the values does not appear and instead those pixels ...
-1
votes
1answer
34 views

Select polygons (A) that contain polygons (B) by using R code

I am wondering how to select polygons (A) that contain polygons (B) by using R code. B<-readOGR(dsn="H:/AP", layer="WWTP") A<-readOGR(dsn="H:/AP", layer="catchment")
1
vote
2answers
307 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 ...
4
votes
2answers
5k views

How do I set the fillcolor of polygons in Leaflet.js dynamically?

I'm using the interactive chloropath example for leaflet.js I figured out how to make each of my polygons add a running tally of values to the bottom of the page after each polygon is clicked. Upon ...
0
votes
1answer
7k views

Merge attribute of points into a polygon : Arcmap 10

I have points layer which the attribute looks like this: FID Shape ID Lat Long 0 Point 2065 -5.51666 106.48333 1 Point 2319 21.93333 120.73366 I also have polygons layer : FID Shape ...
1
vote
0answers
38 views

Using SVG file to fill polygon using QGIS- problem

I try to fulfill polygon with SVG file (which created with inkscape) but when i load the file into QGIS by this way: i get polygon layer with no symbology: Now, i red Using SVG from Wikipedia ...
1
vote
1answer
186 views

How to select all polygons where neighbor vertex points are below a distance threshold in arcmap

I have a shapefile with over 100k polygons (some of them have holes in them but apart from that they are simple polygons - no multipart). I want to loop through all of these polygons and select only ...
1
vote
1answer
52 views

How to calculate the area of polygon features within another polygon feature layer

As shown below, I would like to calculate the percentage of each red feature (landscape zones) taken up by a green feature (forest zone). So I need the summed percentage of forest zone for each ...
7
votes
3answers
831 views

Lossless Polygon Simplification?

Is there a standard/recommended algorithm for simplifying a polygon without shrinking any of its original boundaries? Right now I'm using TopologyPreservingSimplifer within JTS and running into ...
2
votes
1answer
57 views

Getting polygons out of multi-polygon GeoJSON files?

I am a farmer and very new to GIS. I am trying to load shapefiles or KML files to an online site/service called FarmLogs.com. Once my "fields" are uploaded the site can tell me the amount of ...
2
votes
3answers
929 views

Iterating polygons on a SpatialPolygonsDataFrame in R with readWKT

I have fetched some data (39 objects) from my PostGIS database and converted this data into a matrix: rs <- dbSendQuery(con, "SELECT ST_AsText(polygon_accumulation) AS ShapeWKT from accumulation;")...
1
vote
1answer
46 views

Plot multiple buffers around points

I have three buffer radius sizes radius<-c(1000,700,500) that I have placed around an array of points (two example points are given here in the file SourcePlace). What I'd like to do is ...
0
votes
1answer
31 views

Extend polygons to match another polygon in ArcGIS

I am struggling with this task :( I have various layers, all having a common outer shape (see the blue polygon in the picture). On of those polygons however, has a different shape. I somehow need ...
3
votes
2answers
71 views

PostGIS - Get a point inside a line or polygon

I need to get the center point of a line or polygon to make marker for my app. So that when you click a marker the geometry appears (line or polygon). I used ST_Centroid to make it work. The result ...
0
votes
1answer
31 views

Auto-Create polygons from Geo-referenced PDF

Is it possible to automatically create polygons/features from a georeferenced PDF? I'd like to geo-reference an expanded view of the below linked pdf, and then have each of the tracts created ...
1
vote
1answer
58 views

In QGIS is there a way to make one polygon out of several

I'm trying to use QGIS to get a more simplified vector country data. For example Canada has several bits to the north all as separate polygons where as I'd be happy to just take a rough outline of the ...
2
votes
1answer
49 views

Make square polygon from one point and area

I have a shapefile of points with a variety of attributes, the relevant ones being "ID", "area", "lat", and "long". Such as... The lat/long coordinates are always the SW corner of a plot and the area ...
1
vote
1answer
25 views

Wrong boundary when plotting Canada's shapefile in Python

I want to plot the Canadian shapefile with province boundaries highlighted and hollow filling. I have downloaded the shapefile from here. This is the script I use to visualize the shapefile: ...
2
votes
2answers
30 views

Postgis meassuring distance between first and third points of a polygon

I am using ST_DumpPoints() function first to get the list of the different points in the polygon but after doing that, the first point is in one record and the third point is in another record and I ...
0
votes
1answer
24 views

Carto DB city border polygons issue?

I want to visualize some statistical data about my country and I'm using the CartoDB geocoder. I've city names and I want to see cities as polygons but CartoDB says it has no polygon data, it can only ...
7
votes
5answers
6k views

Easy way to create a boundary polygon shapefile from a set of LAS files using ArcGIS 10?

I have a bunch of LAS file sets that I need to process. The current task at hand is to generate a "footprint" shapefile that contains polygons for each LAS tile. I am looking for a graceful way to ...
6
votes
2answers
9k views

Createing polygon layer from point data using QGIS?

I'm currently using QGIS 1.8.0 I would like to create a polygon layer from a point dataset, where the size of the polygons relates to the resolution of the grid reference. The ultimate aim would be ...