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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39 views

Display Google Maps Polygon Edge Distances in Meters?

How can I achieve this using the Google Maps API? The meters on each side.
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2answers
61 views

Dissolve tool misses out two polygons

I'm trying to dissolve polygons based on a code number in the attribute table. It all works well, with an exception of two polygons that fail to dissolve - they literally drop out from the output. It ...
0
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1answer
440 views

Reverse geocoding polygon co-ordinates?

I have a large dataset of polygons for property sections that I need to reverse geocode. It was recommended that I use a GIS like Quantam to do this however from my research I am not 100% sure if a ...
1
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1answer
54 views

QGIS 2.4 How to label a polygon

I have tried labeling a polygon using the layer properties>label function but it doesn't show my label. How and where do I type the text I want and get it to show?
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2answers
7k views

How to calculate polygon areas and perimeters using QGIS?

Using QGIS, if I load a polygon layer and make a new column, how do I fill that column with the: area of each polygon and another column with length of the perimeter of each polygon?
3
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2answers
237 views

Overlaying polygon filled with solid colour with diagonal lines in QGIS

I'm making a vegetation survey map using the UK phase 1 survey colour codes. The code for marshy grassland, for example, is orange overlain with purple diagonal lines. For the moment I've created ...
2
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3answers
1k views

Intersect (analysis) of polygons generating empty output

I have previously asked a question on determining the area of polygons with another polygon boundary. Determining the area of each polygon within a polygon boundary? I came to the conculsion that ...
2
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1answer
128 views

Clipping Line shapefiles within extent of Polygon shape?

My question is an extension of Vertical lines in a polygon shapefile. Kindly refer to that question first. What you shall see there is a method of generating vertical lines with respect to the ...
3
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1answer
23 views

Bringing attributes of multiple polygons into other polygons?

I need to absorb multible attributes included in block areas into a number of ploygons. In other words, I need to bring block level data into a number of overlaying polygons. The polygons will absord ...
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1answer
82 views

Intersecting Overlapping Polygons Individually in ArcGIS

Map Layers: -Census Tract Shape File w/Population Data -Set of Store Locations with 5 Mile Buffers (Significant Overlap Between Buffers) I have create feature layers for both and I am trying to ...
2
votes
1answer
47 views

Joining QGIS extent table with shapefile

I used QGIS to find the extents of a list of features from a census boundaries shapefile. I used Vector - Research tools - Polygon From Layer Extent, which creates a new shapefile with a table of ...
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0answers
53 views

Create Polygon with inner polygons from KML or Shapefiles?

I am creating a windows forms application and I want to create a polygon from a KML or Shapefile as a layer on top of a Google Satellite map. Today I am using GMap.NET that got an polygon object but ...
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2answers
98 views

Vertical lines in a polygon shapefile

I am working with a GIS problem using a single input of a polygon shapefile. Consider an irregular polygon. I want to draw vertical lines across the extent of the polygon at equal spacing. How I ...
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0answers
97 views

How to convert multipolygons to a single polygon

I have converted a set of gps points to polygon and then using .makevalid() I saved them in sql server.But It converted them to multypolygons.Is there any way to fix this problem and convert them to ...
0
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1answer
304 views

Zip code highlighted in google map

When we search for a zip code in Google Maps we get the area highlighted in the map with a dotted border. How is this calculated? How do they know how to draw the polygon? I'm looking at implementing ...
2
votes
2answers
455 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 ...
6
votes
1answer
190 views

Select by location of doughnut hole polygon

I have vectorized the Corine Land class raster and want to select certain classes that are "inside" other classes. How can I select the polygons circled in blue? All the select by location options ...
1
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1answer
55 views

Converting rasters to polygons through cell centers

With arcgis, it is possible to convert a raster image to a polygon representing the boundary of the raster using the Raster To Polygon tool. The output polygon will follow the cell edges of the ...
1
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0answers
131 views

Convert polygon data into extreme lon/lat coordinates using QGIS

I'm very new to QGIS. I have a shape file of census blocks and want to use the data to plot points within each boundary using Google Maps api. I figure the best way to do this is to find the extreme ...
1
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1answer
84 views

StArea() in sqlserver is in which unit?

I have a problem with saving STArea in sqlserver. Here is a query where I get the area of a polygon: select Geometry::STGeomFromText('POLYGON ((51.3386535086000000 31.7951253522000000, ...
5
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0answers
371 views

Grouping analysis of points to divide a polygon into n number of sub-regions

I'm attempting to create n sub-regions from a polygon based on a cluster analysis of a bunch of overlapping raster layers (physical layers, eg: depth, currents, waves). Briefly, I can create a ...
5
votes
4answers
7k views

Getting polygons of all countries and ISO-3166-2 subdivisons

In order to do reverse geocoding lookups to find a country (as ISO-3166-1) and the subdivision (as ISO-3166-2) for given coordinates I am looking for a way to get all polygons of all countries and ...
2
votes
1answer
286 views

Converting set of points to polygon using C#?

I want to convert a set of gps ponints to polygon.I used a simple loop to convert it to a WKT and than used makevalid() in sql server and save it in a gemetry column in databasae.Is this way right?or ...
4
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2answers
112 views

How to programmatically delete all inner rings of a polygon layer?

I have many polygon layers, each layer containing many polygons with inner rings. I know that you can delete a ring manually with QGis (Edit -> Delete ring). I need the python equivalent to ...
0
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0answers
48 views

Is there a way to set different levels of transparency (opacity) for a polygon's border and its interior?

I have some polygons which I'd like to display with their interior displayed at a higher transparency than their borders. Right now, I am doing it by creating two separate layers with the same data ...
3
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1answer
138 views

Displaying adjacent polygon lines beside each other instead of overlapping

I would like to display adjacent polygons with the line work beside each other, not one on top of the other for that shared boundary. I do not want to edit the polygon boundaries - only want to ...
9
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2answers
331 views

Creating an “average” polygon

I found this thread in the old ESRI forums with the same type of problem I am facing today. The solution to the problem is explained in little detail and since I am not an expert, I was wondering if ...
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1answer
27 views

Intersection of triangle and polygon

I have a triangle and an arbitrary polygon lying on the same plane in 3D space. I need to find the fastest way to determine if these two intersect, one is inside the other, or completely separated. At ...
3
votes
2answers
66 views

Counting number of points in particular polygon for list of individuals using R?

I have distribution points for a set of individuals and a file of polygons-with matching IDs. What I would like to do is to go through and for each individual find the total number of points and the ...
8
votes
3answers
5k views

How to smooth/generalize a polygon in qgis

Is it possible to smooth or generalize a polygon in qgis? Ìs there a plugin available like the generalizer-plugin for lines? I could convert my polygons to lines, smooth them and convert them back to ...
1
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1answer
74 views

hiding some “feature”s in GeoJSON file on map

I have geojson file including boundaries of most countries in world. When I clicked on a "feature" (aka country, or polygon) I want to hide it while keep showing the others. because I am planing to ...
2
votes
1answer
79 views

JTS “points must form a closed linestring”

I'm trying to create a polygon and calculate it's area using final GeometryFactory gf = new GeometryFactory(); final ArrayList<Coordinate> points = new ArrayList<Coordinate>(); ...
1
vote
1answer
59 views

Split a polygon based on density of points in ArcGIS 10.1

I have two layers: Polygon layer representing administrative boundaries Polygon layer representing topography (i.e. a map) In some of the administrative areas, the buildings (shown in the map) are ...
0
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1answer
38 views

Using ArcGIS Polygon to Raster tool does not divide resulting raster on cells?

I try to create raster composed of small (5x5 m) cells (pixels) from a polygon in ArcGIS-10. I created a polygon (as a single object), and use Feature to Raster Tool and Polygon to Raster tool (of ...
2
votes
2answers
66 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
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1answer
37 views

Filtering out a subpart of a polygon shape file

I have ArcGIS 10.1 for Desktop software. I am working with a polygon shape file (having n rows) in ArcMap. The project demands splitting this file into two polygon shape files having n1 and n2 rows ...
0
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0answers
38 views

Splitting existing polygons with existing polylines(roads) with GME tool “split polygon by lines”

After reading through many of these articles i believe the GME tool "split polygon by lines" should be useful to my problem. I have a polygon that needs to be split by a road layer. When i run this ...
0
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0answers
36 views

openlayers clickevent for undercoat features polygon on multiple vector layers

I'm using two timers that give me coordinates and some data for my features (Sensors(de Sensoreinheit) & receiving unit (de Empfangseinheit)), deleting all features on the Layers and placing new ...
2
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0answers
36 views

Dividing a polygon into two OpenLayers

I'm using OpenLayers to draw a polygon to my users. I want the ability to implement through a line, split the polygon into two, with the cutoff line that the user drew. Does anyone know if this is ...
3
votes
2answers
130 views

Creating an outline around groups of polygons

I am trying to find a tool or workflow for creating a type of minimum bounding polygon or envelope for complex land areas. (Not just a rectangle, but a simplified perimeter) Can anyone recommend a ...
2
votes
0answers
70 views

Using R to subtract the polygon area of one shp file from another

I'm looking to produce a map from two separate maps in R. My Maps files are as follows: ftp://ftp.cpc.ncep.noaa.gov/GIS/us_tempprcpfcst/610prcp_20140822.zip #Map1 ...
1
vote
1answer
228 views

Step-by-step: How do I extract Raster values from Polygon overlay with Q-GIS or R?

I am writing my master thesis at the moment and am having the exact same problem as user Curley in this question: I first need to overlay a Corine 2006 raster with a polygon layer (2638 polygons). ...
6
votes
3answers
1k views

Can Polygons be generalized to MultiPolygons in GeoDjango?

I set up a model with models.PolygonField in geodjango, using postgres as database. I try to import shp into postgres. The problem is, shp (compiled with QGIS) mixes polygon and multipolygon, hence it ...
1
vote
1answer
24 views

Area of an EPSG 27700 polygon

I am working with EPSG 27700 polygon data in PHP. All the polygons are in the UK. The polygons do not have holes inside them. I'm hoping to be able to calculate the area of these polygons. For this I ...
1
vote
1answer
53 views

A library to edit geometry in C#

For my windows application, I am looking for a method to edit vertexes and geometry of features that are stored in a SQL Server database. I just want a simple function for dividing polygons into 3 ...
4
votes
1answer
280 views

POSTGIS SQL - How do I remove (defined) sliver polygons

I would like assistance in writing SQL (for POSTGIS in postgresql) to remove sliver polygons (including long narrow slivers and some small irregular polygons that were erroneous 'gaps' in the original ...
1
vote
2answers
125 views

Making single polygons from a shapefile

I created a shape file a while ago with several (20+ polygons) in it. I was wondering if there is a way to symbolize these polygons with unique symbols. Basically all I actually want to do is color ...
3
votes
1answer
69 views

How do I save a polygon once I have created it in editor?

I am attempting to create a new polygon. I go to ArcCatolog>New>Shapefile and make sure Feature type is set to polygon. I create the polygon and if I click save edits or stop editing, it disappears. ...
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vote
2answers
46 views

Adding polygons from an existing layer to a new layer (shapefile)?

I have an existing shapefile that contains parcel data. I would like to add some of the existing parcels to a new shapefile. I am using ArcMap 10.1.
5
votes
2answers
2k views

Converting Longitude and Latitude Coordinates to Square Miles?

I have a set of Long and Lat co-ordinates making up a five point polygon which I have converted in excel using the following formula: ...