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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5
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3answers
5k views

Filling in Donut Polygons using ArcGIS for Desktop?

I have a set of polygons that represent bodies of water. In the same feature are polygons that are the islands in the body of water. So for a given lake, there are smaller polygons within that ...
4
votes
2answers
603 views

Including polygons as part of network for ArcGIS Network Analyst?

I am creating a pedestrian walking network of a downtown area. I am digitizing line segments for paths and sidewalks, but I need to incorporate parking lots into my analysis. So far, I have been ...
3
votes
2answers
54 views

problem merging polygons based on a column value - using Spatialite

edit: as I am unfamiliar with any tools I decided to try my luck with PostGis. I imported my data. and executed the query : create merged as select delomrade_code, st_union(geometry) from grunnkrets ...
1
vote
0answers
30 views

Joining polygons with same boundaries

Sorry if my question feel stupid but I'm a new QGIS 2.4 user. My shape is composed of 7 polygons which are supposed to be adjacent (ie sharing sharing same nodes). Would like to join the polygons by ...
3
votes
1answer
61 views

Find small polygons inside big polygons

I'm trying without success to find a solution for problem in ArcGIS and this is the reason that I'm sending this message. I have one polygon shapefile with postal codes for South Africa (no Gap, no ...
3
votes
1answer
139 views

Highest DEM pixel in polygon

I'm working with QGIS and have a big DEM raster layer with height information and a vector layer with many polygons, representing 1 x 1 degree tiles. Now I want to find for every polygon the highest ...
2
votes
1answer
92 views

How to remove columns in a spatial polygon data frame in R?

My spatial polygon data frame (spdf) contains too many columns (variables) and I want to remove most of the columns entirely. I know how to do this with a regular data frame in R, but I am unsure how ...
3
votes
1answer
338 views

Why is ArcMap 10.0 editor deleting some added vertices and simplifying polygon?

I am using ArcMap 10.0. I am trying to edit (and add) vertices in a polygon. I start editing, (using "Edit Vertices" tool), and add many vertices in the polygon. Then when I am done, I save the ...
1
vote
2answers
37 views

QGIS Convert Polygon M to polygon

I have been using Argis 10.1 and been able to convert polygon m to polygon shapefiles. I would like to do this with QGIS but I am having difficulty in finding the correct tool to do so. Please Help
1
vote
1answer
55 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 ...
3
votes
3answers
305 views

How to export polygon coordinates to CSV (not WKT)?

I am new to QGIS, and I am now trying to export polygon coordinates from a shape file to a csv file, but so far all my attempts have failed. I have found numerous questions and answers about this, but ...
1
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0answers
39 views

spatialpolygons heatmap in R - NAs in grey?

I have a spatial polygon data-frame and I am trying to plot a heatmap via spplot. It's a map of Europe and the values for the heatmap are in a column of the data-frame. Plotting it works fine but I ...
1
vote
1answer
87 views

Automating Intersect between two polygon layers

I have a spreadsheet that has county-level occurrences of around 1000 species within the US in the column headings (Species State County). Thus, for some counties there may be multiple species. I ...
1
vote
0answers
39 views

Way to split and create buffer space between polygons in QGIS or ArcMap

After performing a feature extraction of rooftops, some of my buildings have been joined together as one polygon. I want to split these large polygons so that each new division is only covering one ...
2
votes
0answers
42 views

How can I merge adjacent polygons and return all (adjacent and not adjacent) as Multipolygon?

I have a postgres database with administrative boundaries and their geometry. Each of those boundaries have an ident number. What I want to achieve: First I want to select all rows which are ...
1
vote
1answer
29 views

Determine changes in land cover of isolated features over time?

I have a a study area of 2 Landsat scenes from 2013 which were classified for a specific natural community, and these areas have been isolated and extracted and digitized into vectors so that they can ...
0
votes
2answers
2k views

QGis: Merge intersecting polygons into one which are part of the same feature

I'm not a GIS professional so I hope I use the correct wording, at least I hope you understand my question. Let's say there are 5 polygons in the feature A. In the shape file there are more ...
2
votes
1answer
76 views

How to do a “fuzzy” intersection?

I have two layers that look like this: I want the intersection (or whatever the correct term may be) to look like this where the output polygons are the same as the original base layer, just with ...
2
votes
1answer
74 views

vb.net ArcObjects is there a function the same as “Select Features by Polygon” of ArcMap's tool

I want to know whether there is a function provided by ArcObjects (vb.net) to realize the "Select Features by Polygon" on ArcMap (shown below). I am using VS 2012 (vb.net) and ArcObjects 10.2.2, ...
2
votes
1answer
123 views

Check if line crosses a polygon

What I'm trying to do is with JSTS to check with lineGeom.crosses(polygonGeom) function if a line is crossing completely a polygon. The problem is that both cases from the picture returns true. I ...
0
votes
1answer
53 views

Cannot obtain correct area values *With* correct projections

I'm trying to get the percentage of each U.S. county overlaying groundwater (data from the census and USGS respectively). They're both polygons. I have 1) correctly projected the data and the layer ...
0
votes
3answers
59 views

Counting building polygons in neighborhood polygons

I have two layers, one of them is neighborhood data and the other is the buildings in the city. I want to count the buildings in a neighborhood (by using borders) and add this value to the ...
0
votes
1answer
67 views

The best way to convert points to polygons using ArcObjects

I have a set of points from GPS I want to convert them to polygons..I have two approaches to do this.1- convert points to polygon..I do this with below code: private IPolygon ...
1
vote
2answers
29 views

polygon to raster - not all polygons rasterized

I have a building footprint shapefile (polygons) that I want to convert to a raster. I use the Polygon to Raster tool, and specify a cell size by importing from another raster (which is 24m x 30m). ...
2
votes
0answers
25 views

Polygon parcel division in python

Is there an open source tool or module in python that does parcel division of polygons like in ArcEditor?
3
votes
2answers
110 views

Determining closest representation of polygon as collection of points+radii

Have a bit of a tough question, which I realize there may not be an easy solution to. Figured what better place to ask. I'm attempting to transform a polygon into a series of arbitrary points with ...
1
vote
0answers
47 views

How to understand google map overlay type from object (polygon or polyLine)

var Line = new google.maps.Polyline({ path:predectionArray, editable: false, strokeColor: '#FF0000', strokeOpacity: 1.0, strokeWeight: 2 }); var Rect=new google.maps.Polygon({ ...
0
votes
0answers
63 views

Creating a polygon around features

I want to create a polygon around a number of points so that all the points occur within the polygon. The purpose is to do this to a number of different features and see where they overlap.
2
votes
3answers
103 views

How to highlight polygons within another polygon?

I want to symbolize public buildings in OSM data. For Example: There is a polygon and in column "amenity" it has the value "school". But i don't want to highlight this polygon, but the buildings ...
2
votes
0answers
29 views

ArcMap - proportion of polygon in lon/lat grid cells

I have a polygon representing a river basin on a 1 X 1 degree lat/lon grid. I need to create a boundary using the grid cells as the boundary to best represent the outline of the basin. I would like to ...
9
votes
5answers
1k views

Where can I get neighborhood boundaries?

Besides Zillow's creative-commons licensed neighborhood boundaries shapefiles, what sources of neighborhood boundaries are there? Not just in the US, but all over the world. Free/open source is ...
0
votes
1answer
51 views

ArcGIS10 Highest point via polygon features

I am using ArcGIS 10.0 with 3D Analyst, Spatial Analyst and Military Analyst. I feel like I am halfway to solving a problem but do not seem able to completely solve it. I have a polygon shapefile ...
2
votes
2answers
223 views

How can I split a multi-part polygon into single polygons?

i want to split a multipart polygon which consists of several polygons into single polygons so I can delete each polygon without deleting them all at one time. I am using ArcGIS 10.
0
votes
1answer
58 views

Determining direction of longest segment of polygon?

I have a shapefile with 9000 agriculture fields and what I like to do is to determine for each field (=each polygon) the direction of the longest segment. For instance, the selected polygon in the ...
1
vote
2answers
38 views

How to extract a new linestring vector from a existing multipolygon in QGIS?

What I want to do: create a new line (named linestring in Postgis?) from existing multipolygon layer in Postgis. Purpose: once these lines are created, I'll run some distance calcs from specific ...
0
votes
1answer
86 views

How to create polygon feature class from UTM coordinates?

I am working to create a polygon from UTM coordinates. The script I am using fails with a "must be a sequence, not float" error: Traceback (most recent call last): File "F:/sample/clipTiles.py", ...
1
vote
2answers
47 views

Split polygon based on line segment

I am trying to split a street polygon based on the segment ID of the street, giving them the same segment_ID in the attribute table of the street lines. I did not use the line feature class to derive ...
2
votes
1answer
30 views

How to subtract lines with thickness from polygon

I have a polygon and some lines crossing it. I want to subtract the lines with a certain "thickness" from the polygon, so it splits up into various polygons which do not touch each other anymore. You ...
4
votes
0answers
45 views

Is there a limit to the number of polygon points you can export to CSV in QGIS 2.4?

Using QGIS 2.4 I am currently importing a csv file with ~30,000 polygons (polygons in WKT format). I also have a United States shapefile. I have used the Clip function to get only the polygons that ...
0
votes
2answers
64 views

Tool for rendering/drawing maps from coordinates

What tools can be used to convert a set of coordinates into polygons? For example: this code represents a room by providing information about it's four corners. <node id='-202' lat='41.015146' ...
0
votes
1answer
44 views

How to split Polygons by line grid?

I want to split a polygon by a intersecting line into different parts, exactly like in this post(Qgis - Is there a way to split a polygon layer with a line layer?). I have a vector grid to cut the ...
0
votes
1answer
127 views

accurately find the bounding box of geography polygons

Im displaying polygons on a map and have had issues with the spatial index where the index performs well only for certain data sets (large areas with low density / high density small map areas). I've ...
2
votes
1answer
65 views

Retrieving points that make up drive-time polygon generated by ArcGIS for Desktop in automated way?

One of our GIS guys showed me a demo of the ArcGIS Network Analyst extension creating a drive-time polygon for points that he clicked on a map. This is exactly what we need for our web application, ...
3
votes
2answers
96 views

Splitting worldwide roads into multiple road datasets with less than threshold number of features?

I want to split a worldwide 'road dataset' into multiple grids/blocks-extents, depending on the amount of features resides in that block-extent. If the amount of features(inside that block) is still ...
0
votes
2answers
190 views

Convert polyline to polygon Using ArcObjects

I have a polyline and I want to convert it to a single polygon feature,I used this code but I get error while I can convert the same shape file using feature to polygon on ArcGIS Where is my mistake? ...
0
votes
1answer
56 views

How do I overcome this problem of converting a raster layer to polygon form?

I am trying to convert a raster layer of U.S. climatic regions into polygon format using ArcMap 9.3 under Windows XP. The original data are to be found at the following address: Koppen Climate ...
1
vote
1answer
51 views

Appropriate pixel size when converting vector to raster

I am converting vector polygons into raster datasets. Is there a standard calculation for converting the scale of the vector into an appropriate pixel size (e.g. 25 metres)? My vector has been ...
1
vote
0answers
49 views

Merge overlapping GeoJSON GeometryCollections

I need to merge three overlapping GeoJSON GeometryCollections of Polygon. Ultimately, the end result needs to be a geom type for PostGIS (e.g. MULTIPOLYGON) so I can easily check if particular points ...
2
votes
2answers
74 views

QGIS polygon centriods - How are they created?

I have been using QGIS to analyses spatial data and I created polygon centroids with the vector geometry tools. Now for a report I have to explain how these centroids were created. I have not been ...
0
votes
3answers
59 views

Same size polygons giving different overall areas

I am currently working with multiple shape files that I have clipped to the exact same extent, but when I calculate area (acres) within each polygon. I am getting different results between the ...