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
1answer
345 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 ...
1
vote
2answers
247 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 ...
2
votes
1answer
177 views

Dynamically drawing a polygon around another shapefile, ArcGIS 10.2

Let's say I have a vegetation raster that indicates the density of forest all over the world. I also have a shapefile that contains the admin boundaries of each country in the world. The easy part is ...
0
votes
2answers
122 views

How to combine multiple zipcode polygons into one polygon

In CartoDB, we have a table of chapters that make up a national organization. Each chapter record has a polygon that defines the geographical area that the chapter covers. The area a chapter covers ...
0
votes
2answers
230 views

Zipcode to Polygon/Boundry

Is there any API out there which can give me Polygon value for a zipcode? I really thought that it would be fairly easy for me given the number of Maps APIs out there. Either Google Maps API or ...
1
vote
0answers
48 views

PostGIS: intersection of a polygon with 2 rasters

I'm trying to get the intersection of a Polygon with 2 raster layers in PostGIS. The rasters have the same size and pixel size and I'd like to retrieve for the polygon a list of something like that: ...
2
votes
4answers
7k views

Understanding the polygon handler function in Openlayers

Using openlayers, I want to be able to draw one polygon on a map. After one polygon is drawn, I want an event to fire that stops any more from being drawn until a button is pressed. My current code ...
0
votes
0answers
36 views

Query to merge simplified polygons according to the map scale-factor

I'm trying to construct a view in PostgreSQL that simplify polygons according to the map scale-factor. Basically I was reading this thread ...
0
votes
1answer
74 views

Draw polygon with GUI

I'm looking to make a python add in tool for ArcMap to draw a polygon. Eventually I want the tool to also calculate the area and a bunch of other things but for now I would be happy just drawing an ...
2
votes
1answer
247 views

Split polygon into several smaller polygons in QGIS

I have a layer of polygons depicting response boundaries, I would like to break each of these polygons into a number of sub-polygons. As this is for an exploratory project, the polygons themselves ...
2
votes
2answers
994 views

Converting polygon layer to *.txt files using ArcGIS Desktop?

Is there any way to convert polygons that do not have coordinates in the attribute table to a txt file with coordinates. I will be using the txt file in a different software (not ArcGIS), so I need ...
1
vote
1answer
179 views

Overlapping polygons in the same layer

I am working in QGIS on a vector layer where areas are classified using an attribute "typo". The problem I'm encountering is that many polygons are duplicated or overlapping, with the result that some ...
0
votes
0answers
6 views

How do I search for features within a polygon in EarthExplorer or other freely available tool?

In USGS EarthExplorer, I'm trying to search for cemeteries within a defined area using a polygon created in Google Earth. If I select cemeteries under features, it clears that selection when I load ...
2
votes
1answer
45 views

Rotation of polygon fill symbol using ArcGIS for Desktop?

In ArcMap (ArcGis 10.1) I'm trying to find a way to fill a polygon with a symbol in different orientations. Is it possible? Example: look at the red semicircles, I would like to do something like ...
6
votes
3answers
303 views

Filtering features using geometric attributes of polygons in ArcGIS Desktop?

Given a polygon featureclass containing many polygons of different sizes and shapes, which geometric attributes (area, perimeter, etc) could be used to filter the polygons? It's probably best to ask ...
1
vote
4answers
77 views

Finding polygons which are within/intersect other polygons using FME?

Version: FME Desktop 2014 SP3 I have two shapes with polygons. Now i want to locate those polygons of shape A (polygon.shp) which intersects polygons of Shape B (POLYGONS) (or are within them). I am ...
16
votes
6answers
6k views

Generate points that lie inside polygon

I have polygon feature and want to be able to generate points inside it. I need this for one classification task. Generating random points until one is inside the polygon wouldn't work because it's ...
0
votes
1answer
37 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 ...
1
vote
0answers
31 views

XYZ bounding box of a spherical polygon

I'm looking for an algorithm to calculate the 3d bounding box of a spherical polygon - i.e. the min/max X, Y and Z over that part of the surface of a unit sphere. The purpose is to aid fast ...
0
votes
3answers
27 views

Make polygon from area not covered by loaded polygons (like invert selection)

See screenshot, from geojson.io, with a geojson file loaded: So how do we make a polygon out of the blank area? Looking for a way which doesn't involve manually copying selected sequences of ...
9
votes
1answer
3k views

Polygon label repeated for each tile

I'm using the standalone GeoWebCache to serv tiles from a remote GeoServer. My problem is that the polygon label is added to each one of the tiles served, instead of only once in the polygon centroid. ...
1
vote
0answers
20 views

Lines > Polygon artifacts

I am trying to make polygons from a set of boundaries from an SVG file with closed polylines I downloaded off wikipedia. 1) convert SVG to DXF via Inkscape 2) import into QGIS (shows polyline data) ...
0
votes
2answers
267 views

Problems with Polygon Reshape Feature [closed]

I've created a polygon and closed my project, after opening the project again, i can't use the Reshape Feature tool in that specific polygon. But if I create a new polygon in the same shapefile I can ...
1
vote
0answers
17 views

Shaded KML overlays on OSM tiles in QGIS?

This seems simple - but the solution is escaping me. I have a series of dynamically generated KML files describing simple, shaded polygons, with each polygon having a slightly different (externally ...
1
vote
0answers
47 views

Polygons in Polygons

I have 2 layers, they represent 2 different data. I did a spatial join to see the polygons that fall in the other layer using the match option as identical. Before, i used the intersect as the match ...
0
votes
0answers
13 views

Cut polygon with polygon QGIS [duplicate]

I have two polygons. One sits mostly within the other (pink) and I would like to cut this from the other polygon (blue). This is a feature I have used before in MapInfo but struggling to find the ...
0
votes
0answers
12 views

Dynamic polygons grid with specified area based on raster

I'm interested if anyone have idea how to automatically create (maybe in R?) dynamic grid of polygons with specified approx. area (for example around 20000 m2) based raster data or points with values ...
3
votes
3answers
276 views

How to change 0,360 WKT string to -180,180?

I'm reading POLYGON WKT strings using OpenLayers.Format.WKT().read(). The polygons use 0,360 longitudes but my map is -180,180. When I display the polygons on the map they are displayed outside of the ...
0
votes
2answers
57 views

Extracting multiple values of raster to polygons using ArcGIS for Desktop?

I was hoping I could get some help on how to extract information from a land use raster using polygons. I have a layer with 157 polygons and a land use raster with multiple land use categories for the ...
5
votes
2answers
893 views

How to combine data from overlapping polygons?

Here's what I'm working with: Shapefile of the current 32 Congressional districts for all states Shapefile of the tract boundaries for Texas A DBF format table of Hispanic counts and proportions for ...
1
vote
1answer
63 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 ...
2
votes
5answers
2k views

Counting road intersections and blocks

I have a shp file that consists of the road system of Mexico City. I would like to count the number of road intersections (crossings) and blocks (which I would define as a segment starting from one ...
0
votes
0answers
21 views

Finding how many points are in polygon of layer in specific time using QGIS?

I have the layer that I created with the number of earthquakes in each region in the last 400 years. I want to know the number of earthquakes that occurred in one specific region prior to 1900. How ...
3
votes
1answer
286 views

Area-weighted rasterising of polygon data

I'm looking for any GIS tool to do detailed rasterising of polygons. I've checked GDAL's gdal_rasterize command (and API), and ArcGIS's Polygon to Raster tool, but they only rasterise 1 attribute per ...
0
votes
1answer
22 views

Double Entries/ Errors with Digitizing Polygons

I have a layer that has errors, i mean polygons have double entries (digitized twice), i can edit manually but there's a lot of attributes and it will take ages to clean the data. Is there any short ...
0
votes
2answers
82 views

Get Area size using Dragbox in Openlayers 3

I need to be able to show the square meters of an area using dragbox. There's a great example using draw polygon, but I need to limit users to a regular rectangle. The formulas and SHOULD be the ...
1
vote
1answer
51 views

Make diagonal grid in QGIS, divide square into squares

I have square polygon which is aligned under some degree and I want to divide this square to, for example, 25 smaller squares, which must be under the same degree in this square polygon. How this can ...
0
votes
0answers
16 views

calculating total area of multiple polygons in qgis [duplicate]

I wish to know the total area of all polygons within a shapefile layer. So far I have added a new column to the attribute table that shows me the individual area of the polygons.I tried to copy the ...
2
votes
3answers
146 views

Find closest point between polygons inside other polygon

I have access to ArcInfo (ArcGIS 10.1). The dark polygons are settlements. The green polygon is derived from a suitability analysis. The surrounding white area is restricted. I want to find a point ...
3
votes
1answer
96 views

Leaflet JS add GeoJSON shape as a hole in a polygon

I have a dataset which already contains geojson. I can add it to my map with the following line of code. L.geoJson(data.geojson).addTo(map); And I get this But I want to achieve this, where the ...
2
votes
1answer
146 views

Extracting intersection areas in R

I have two polygons. One contains fields(X,Y,Z) and the other contains soil types (A,B,C,D). I want to know what area of every field contains which type of soil. I tried the following: ...
10
votes
8answers
20k 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 ...
1
vote
1answer
26 views

Workflow for updating raster using polygons of different attributes

I require a specific output but it is proving difficult for me to work out a workflow. I have: 1) polygons of new housing developments (356, non overlapping) 2) a 25m raster of land cover I want ...
1
vote
0answers
2k views

How to write a point-in-polygon query for Postgis?

I'm trying to write a query in Postgis which will return all rows where a dynamically changing longitude/latitude point resides within the geometric polygon of that row (in the geom column). This is ...
1
vote
0answers
14 views

Overlapping polygons: how to sum attribute values for areas where multiple polgons overlap [duplicate]

I have what seems to be a fairly simple problem but I cannot find a solution. Any help would be much appreciated. I am working in QGIS 2.8.1. I have a shapefile of polygons, each of which has a ...
1
vote
1answer
77 views

Order a list of points to make a polygon with smooth outer border

I have a function that pulls some lat/longs from a Database and then I put those values in a polygon to see it's shape. The problem is they are so random in position and direction from each other that ...
12
votes
3answers
3k views

Proper way to rbind SpatialPolygonsDataFrames with identical polygon IDs?

What's the proper R idiom for rbinding SPDFs together when the IDs overlap? Note that here (as is often the case) the IDs are basically meaningless so it's pretty annoying that I can't just make ...
1
vote
1answer
53 views

Country border between two points

I am trying to extract country borders between two points, using Python. The border is a Shapely Polygon.exterior or LinearRing, the start and end points are Shapely Points. My idea is the following: ...
0
votes
0answers
35 views

How to arrange polygon in Postgis

I have a lot of polygons in a Postgres database. I want to show the polygons, but in order of the the biggest to the smallest. I used the following code: SELECT ST_Area(area_polygon) as luas FROM ...
1
vote
0answers
29 views

Splitting up a single polygon into many polygons of equal point count

I have point data split into 15 different values and want to split up the (green) polygon into a number of smaller polygons each containing the same number of points so that I can make a chloropleth ...