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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34 views

Map polygon property in one shapefile to polygons in another shapefile with same outer boundary

I have two shapefiles covering a region with the same outer boundary. The polygon shape coverage (tesselation) of the two is different. One file (A) has a property assigned to each polygon. How do I ...
2
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1answer
121 views

create polygons and fishnets of specific size and orientation and buffers

I want to study 6 areas in the field and in order to do so I want to divide each one of them into smaller areas/parts. What I would like to do is find an average square or rectangle area surface ...
5
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2answers
125 views

Automate Splitting Polygons Into Sections

I've searched for similar problems on this topic but can't find a solution. I need to split many, many, many cemetery sections into 8 (mostly) equal pieces each. Each section is for the most part ...
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3answers
65 views

Summarize the total area of land use polygons within map sheets - how?

I would imagine that at least some of you have encountered similar problems to mine and I´d like to hear how you solved them. I have a map sheet index (a grid as a shape file) covering a large area. ...
0
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1answer
85 views

calculate distance between points crossing the antimeridian

How can I calculate the distance between two points (lon/lat) if any of the points exceeds the antimeridian (+-180 longitude)? Im using the distVincentyEllipsoid {geosphere} to calculate the shortest ...
2
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1answer
68 views

Create a custom Identify dialog

How can I check if a point belongs to a polygon? I want to create a custom identify tool with edit option. I am using C# and ArcMap 10. My idea is to click on the polygon (building/park/etc) in ...
2
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0answers
69 views

Merge vector layers to fill gaps in QGIS

I have a zip code map which I added per zip code data too (a regional director for each zipcode), and then dissolved the map based on the director attribute. As you may or may not know, zip codes are ...
5
votes
1answer
202 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 ...
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1answer
54 views

Looking for information on methods or algorithms used to calculate centroid from polygons across software

Looking for information on methods or algorithms used to calculate point centroids from polygons across software. ArcGIS uses a "gravity model" but can someone point me to the math or a paper on the ...
2
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3answers
457 views

Combining different geometry types into same feature class?

I've searched the question in this blog. Maybe I don't use the right words but anyway my problem is not present in any post so I'll try to explain my question by opening a new one. I have a polygon ...
1
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3answers
88 views

polygons to polygon conversion with attribute name [duplicate]

1) I have a polygon shapefile with 1000 multi-part polygons in it. Each Row of the table is a multipart polygon. 2) I need 1000 shapefiles with 1 multi-part polygon in each. 3) Each output shapefile ...
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5answers
4k views

How to determine if a polygon is self-intersecting using either ArcPad 8.0 or ArcMap 9.3.1?

I am try to automate a sync replica mxd a nightly basis. The issue I am running into is that in some the of the AXFs (that I get from the users and check-in) have polygons that are self-intersecting ...
2
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1answer
73 views

Get feature data from lat long input QGIS

In QGIS, I have a polygon dataset with feature data. I would like to extract data from this dataset using a latitude and longitude. To be more clear, I have a list of 1000 coordinates. I would like ...
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0answers
47 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
64 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
463 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
56 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?
6
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2answers
8k 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
267 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
2k 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
148 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
votes
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 ...
0
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1answer
85 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
51 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
64 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
113 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
117 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
399 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
470 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
193 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
58 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
142 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
vote
1answer
108 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
376 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
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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
321 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
votes
2answers
149 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
53 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
votes
1answer
154 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
votes
2answers
335 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 ...
1
vote
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 ...
8
votes
3answers
6k 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
vote
1answer
87 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
102 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
63 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
votes
1answer
40 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
68 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
49 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
44 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 ...
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0answers
38 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 ...