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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0
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0answers
38 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
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3answers
99 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
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0answers
19 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 ...
2
votes
3answers
181 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 ...
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
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1answer
46 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 ...
1
vote
2answers
157 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.
1
vote
1answer
47 views

How do I peform a true GIS Clip of polygons layer using a polygon layer in R

I would like to do a true GIS Clip in R of soils polygons using a series of single boundary polygons, but I cannot find an R function to properly do it. It should work just like the CLIP function in ...
0
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1answer
46 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 ...
0
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1answer
276 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 ...
1
vote
2answers
23 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 ...
2
votes
1answer
103 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 ...
0
votes
1answer
218 views

How to calculate the percentage of distribution in each polygon?

I have binary map for disease suitable area and I want to calculate the percentage using pixel count in each polygon how can I do that? I use zonal histogram and do have frequency for each polygon is ...
0
votes
1answer
318 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 ...
0
votes
1answer
30 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
24 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
25 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 ...
3
votes
0answers
13 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
50 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
25 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
21 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
45 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
93 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
76 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? ...
3
votes
1answer
161 views

digitizing (tolerence) error in line data

I have designed a large number of boundaries. For accuracy, I took lines in patches from different data sets and merged them into one. Now I want to turn them into polygons from lines. I every second ...
0
votes
2answers
131 views

Calculating minimum/maximum width for overlay of two polygon strips in ArcGIS or some Opensource GIS

Is there some solution for calculating minimum and maximum width for overlay of two polygon strips? When I clip these strips the result is another strip with variable width about 1 km and 20 km long. ...
8
votes
2answers
256 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 ...
0
votes
1answer
40 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
33 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
22 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
57 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
54 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 ...
0
votes
1answer
12 views

ggmap fortify start and end jumble

I have a census tiger line file for counties available from the Census website. I am trying to display this file on a ggmap, but fortify seems to jumble the regions. I can't find anyone else who has ...
4
votes
3answers
107 views

How to compute the outline of multiple tracks?

I have multiple gps tracks with depth data gathered from the lake. The tracks are overlapping/intersecting. I want to get an outline polygon. I have a multi-line shp. I've tried to diffuse it in qgis ...
0
votes
0answers
31 views

how to remove a point or polygon in shapely python

I want to place minimum number of sensors(circles) to cover a maximum area(polygon). I am using "Shapely",python module. I want to know if a sensor i.e a point buffer inside the range of the other ...
0
votes
0answers
21 views

Why do converting GPS points to polygon using ArcObjects differ from manual converting?

I am working on a project where I have a .gpx file, convert it to a polygon and save it in a geodatabase. I wrote the code and it works fine. But when I rewrote the code in ArcMap using the gpx to ...
0
votes
0answers
15 views

USA MSA/City/County with SImplest Border in JSON

I deal with a lot of poloygon-related JSON representing US places regularly. One thing that could make reading JSON with my eyeballs easier is having a short list of US places whose borders have ...
7
votes
1answer
1k views

How to select WFS features by polygon in OpenLayers?

I need to be able to select features on a wfs layer using a polygon instead of a box. I was hoping this would be a standard option in the SelectFeature class. Too bad this isn't the case. Any ...
3
votes
2answers
88 views

Add rectangle polygon

I have a polygon shapefile layer. I want to add a rectangle polygon (just like in Arcmap), and another one using the previous polygon edge. I need it to be accurate, my hands do not meet this ...
0
votes
0answers
20 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({ ...
5
votes
1answer
144 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
vote
2answers
38 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 ...
0
votes
1answer
17 views

gdal_rasterize : getting area not in or touching polygon (options -at and -i)

I would like to capture the area that is not in a polygon (option -i) and that doesn't touch that polygon. gdal_rasterize -at will return the polygon + edges, but gdal_rasterize -at -i will not ...
-1
votes
0answers
39 views

how to determine the direction in point-in-polygon

I am very new to GIS and I am wondering if the following problem could be solved or not. Given that there are three pairs of points(A<-B, C->D, E<-F) Each pair of points has a direction and ...
0
votes
1answer
27 views

Cut polygon shapefile by line shapefile

I have two shapefiles, a polygon shapefile (lake) and a line shapefile (boudary) I want to create a new shapefile "polygon to the north of the boundary" What tool can I use in QGIS or other free ...
2
votes
2answers
54 views

Check if a single feature is completely within another (arcpy)

I have a feature class that contains one polygon feature, and I need to check if said feature lies completely within another polygon feature. Used selectLayerByLocation and then retrieved the count ...
1
vote
1answer
67 views

Iterating over all features in featureclass to intersect them individually with polygon using ArcPy?

I've got a point featureclass, and I'm trying to individually intersect each feature with a polygon featureclass to get some information about which polygon each feature is in. I did one intersect ...
2
votes
1answer
117 views

Separate a polygon in different polygons depending of the distance to another polygon

I have a reference polygon "R", and others polygons (in grey). I want to separate each grey polygon in multiple polygons, depending on the distance to R with different Buffers : - The red line is R ...
2
votes
0answers
16 views

CartoCSS: Don't show border between adjacent polygons

In OSM, riverbeds are created as multiple adjacent or even overlapping polygons. When styling these polygons in CartoCSS with a border, the overlapping can be seen: I'd like to hide that line ...
-1
votes
1answer
37 views

How do I get the Coordinates of a shapefile into .csv [closed]

I have followed all the instructions on this site, but my output always shows Area, and Perimeter of each polygon. Am I missing something? Should I be changing a setting somewhere to select ...