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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1answer
22 views

ArcGIS: segmenting buffer based on polygon corners

I have hundreds of square polygons which I've created a single continuous buffer around the polygons. What I'd like to try and do is try and break this buffer down into segments based on the corners ...
4
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1answer
39 views

Change feature class from ESRI native geometry to SQL Server geography

Original question: I have found a lot of documentation on importing and using query layers from SQL Server into ArcCatalog/ArcMap/etc. However, when you change the projection of a feature class or use ...
4
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2answers
79 views

How to place only one symbol on the centroid of a multipart polygon?

I am using QGIS version 2.14.1 (Essen). I would like to place symbols on the centroids of my data. The problem is that some of my data has multi-part polygons, which means it places the symbol at the ...
5
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2answers
144 views

Are there any multipolygons in my shapefile?

In QGIS 2.x, is there a simple way to determine if a polygons layer contains multipolygon geometries and if yes: which are these features?
2
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0answers
26 views

Filtering Small Areas of Shapefiles Using R

I'm trying to use the method proposed by the @ialm in the Question "How to speed up the plotting of polygons in R?" There, he loads the maps using getData from the raster package, I tested and it ...
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0answers
21 views

Percent overlaying [duplicate]

I have a raster dataset of points and a polygon features. The two are over the same area and I am trying to find the percent of the raster that overlaps the polygon features. I have tried clip, ...
0
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1answer
40 views

Intersection of a raster and polygon in ArcGIS 10.3

I have two data sets one raster and one polygon. I am interested to see learning the area where the two overlap. I was thinking that I could use the intersect function, but since one of the layers are ...
5
votes
2answers
117 views

How to sum attribute values for areas where multiple polgons overlap?

I have one shapefile with many polygons (at least 100). Each polygon has a value. Almost all these polygons overlap with each other. I want to sum the values of the polygons in the overlappings depend ...
3
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1answer
37 views

Create an optimised path between nodes avoiding polygons entities

I have a point shapefile representing seaports. I have the linear cost of shipping for every seaport pairing (specific shipping cost to go from one point to another point). I want to find a way of ...
1
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3answers
68 views

Comparing size between polygons in different UTM zones

I am going to compare size of different areas in Europe in different UTM zones. The areas I'm comparing are quite small (around 35-50 km2) and I was wondering how to do this the best way? Can I draw a ...
0
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1answer
25 views

Identifying the closest polygon to a point dataset

I have two large data sets one point and one polygon. What I was looking to do was identify which polygon is closest to each point. Hopefully I was looking for a automated process as the point data ...
1
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1answer
28 views

Splitting polygon into multiple fixed-width polygons along edge in R?

I have a polygon and would like to spit into grid with fixed width along with one edge. The result will look like the figure below. Are there algorithm to achieve my target? My language is R, but ...
1
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1answer
28 views

Colour a polygon depending on the number containing of point feature

I have 2 different shape files, polygon and points.I am using QGIS 2.14 as a software. The points are distributed inside of the different polygon shapes. I try to do a categorized map using different ...
1
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1answer
35 views

Checking if point is inside irregular polygon?

I'm using Javascript (https://github.com/substack/point-in-polygon) to test if a point is inside polygon, however I think it's adapted from ...
3
votes
1answer
58 views

Rule based polygon fill in QGIS?

I'm really quite new to QGIS, I want to style polygons fill with raster imagws based on a attribute contained in the property table. What do I have to write in the description in order to get for ...
1
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0answers
23 views

Offsetting polygon borders where they share border in QGIS?

Say you have 2 polygons with different coloured borders, where the borders are shared the colour is problematic. How do you offset/separate them in QGIS 2.10.1?
3
votes
2answers
70 views

Polygon shapefile has irregularities when viewed in ArcMap?

i am using ArcGIS 10.4 for Desktop and when i try loading my shapefiles into the arcmaps it shows extra incorrect lines in my polygon shapefile is there anyway to fix this inconsistencies ...
1
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1answer
39 views

“Direction/Length” Tool not working with Polygons in ArcMap 10.3

My "Direction/Length" right-click option is not working when trying to draw a polygon. I start a shape by dropping a single vertex, right-clicking and choosing "Direction/Length". I enter in the ...
4
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3answers
54 views

Convert .csv with polygon geometry to .shp QGIS

Working on a Mac in QGI 2.12, I have a csv file with polygon geometry coordinates that I would like to save to a shapefile. It displays fine as a csv. However, when I try to use "save as," I get the ...
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2answers
45 views

Animating polygon style over time in QGIS?

I have a shapefile, consisting of polygons. I can join a layer to a database file, and use an attribute (database value) to "style" (color in) the polygons to give me a visual representation of the ...
1
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1answer
18 views

Applying the attributes of polygons to a line segment

I am trying to classify a line segment (pipeline) based off of surrounding features. I have created polygons that contain the necessary attributes (count of total nearby houses) that overlap this ...
0
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0answers
13 views

Converting polygons to contours based on value in polygon table

I have the following and data and have been asked for a map that shows the same data set but displayed as contours. Each polygon has a value in it's table called "count". The "count" field is used to ...
1
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1answer
37 views

JTS: split arbitrary polygon by a line

I just discovered JTS through this stack exchange. I'm looking for a Java solution to cut an abitrary polygon into two by a line. I've implemented one that does fine on convex polygons, but it messes ...
1
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1answer
24 views

Convert KML polygons to lines

I've been given a KML file which should consist of linear features (train lines), but for some reason they're all represented as <Polygon> types. Each appears to have the right data, from end of ...
5
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0answers
54 views

How to decide the master part when you cut a multipart polygon?

I am splitting parts of a multipart polygon in an ArcMap edit session using the cut polygon tool. Is there any way to decide which is the part that will remain multipart and which is the part that ...
3
votes
2answers
73 views

How to get lines into polygons?

I have to create a map with the land register of a place. The data that I already have is unfortunately built out of lines and not polygons. Is there a possibility to create polygons? I already ...
0
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1answer
25 views

Replacing each point in a point feature with a specific shaped polygon

I have many random points in one layer. I want to replace each individual point with a specific shaped polygon like the image below illustrates. Kind of like applying some sort of irregular buffer to ...
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0answers
15 views

StreamingRenderer

I have a problem in my code (Java Geotools). When I draw in my carte map a LineString sometimes when I run my program an errors apears and I don't understand what does it means. Error: avr. 14, ...
2
votes
1answer
41 views

How can I subtract one (very very large) set of features from another?

I'm trying to subtract a very large set of features (water areas) from another, relatively small set of features (land area). In principle, I should be able to do this in QGIS using Vector > ...
5
votes
1answer
148 views

Adding new nodes in the middle of each líne of a Polygon

I am currently working on a Street Lighting Network. I have two layers in PostGIS ( PostGIS 2.1.3 and PostgreSQL 9.3.5): Manholes (56.000 Polygon) Pipes (Linestring) The manholes are perfect ...
0
votes
1answer
36 views

Convert this CSV to a qgis usable format

I have been given a CSV (which has been converted from a RDF). I want to convert the CSV file to a usable format so that I can display these polygons in QGIS. The original file and some other ...
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0answers
31 views

Forcing polyline to offset from polygon border

I am currently working on a site with polygons and polylines and am looking for a way to ensure that the polyline does not overlay the site boundary. I am creating a habitat map and do not want the ...
1
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1answer
32 views

Do we have a way to change the colors of the polygons directly in JOSM?

Do we have a way to change directly the colors of the polygons in JOSM?
0
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1answer
82 views

How can i convert the coordinates (latitude,longitude) to X,Y using postgis

I want know how i can convert the latitude and the longitude coordinates of a rectangle in the Cartesian coordinates, so I can store them in a geometry field using postgis.
2
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0answers
46 views

QGIS : How to calculate centroid on polygons with holes

I try to compute the centroid of polygons with holes on qgis. I did not manage to do it directly, I had to make a conversion to convex hulls before extraction. I crashed my pgsql server trying to ...
0
votes
0answers
23 views

Using the extract function in raster package for R with polygons

I have a shape file that contains some polygons and an unprojected raster. I'd like to extract the cells within the polygons using R, so I use code like this: # Load my polygons MyPoly <- ...
1
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1answer
40 views

How to find the area with most intersection for buffer regions?

Find the area with the most intersection This question relates to previous question asked - How to find the intersection areas of overlapping buffer zones in single shapefile?. I tried to ...
0
votes
0answers
50 views

Leaflet self-intersecting polygons display

Is it possible to set colors of the actual intersections of self-intersecting polygons in Leaflet? Example of such self-intersetions can be found on the pic below, the transparent triangles inside of ...
3
votes
1answer
28 views

How to obtain attributes of a point layer that falls within a polygon layer of different CRS

I have created my own vector grid polygons in QGIS 2.12.2. This creates a new layer to my project, but it's projected in a "generated projection". I want to view the attributes of points that fall ...
2
votes
1answer
69 views

Using Chaiken Method parameters for smoothing polygon vectors in QGIS [duplicate]

I've been trying to smooth a huge polygon, that is result of a segmentation export. I'd like to know what's the best parameters to use Chaiken Method to get smooth curved boundaries on QGIS 2.14. I ...
2
votes
1answer
122 views

How to find the intersection areas of overlapping buffer zones in single shapefile?

Find the intersections of the buffer zones I found an example where they tried finding the intersection of two different shapefiles -Intersect Shapefiles using Shapely. I've tried to adapt my code to ...
7
votes
3answers
1k views

Is there a way to “invert” Polygons?

I have a Shapefile with Polygon features representing the world's land areas (continents, islands). Is it possible to invert these, and get a geometry that represents the world's oceans and seas? So ...
0
votes
1answer
60 views

Python Calculate Cumulative Polygon Areas (Basins)

I've been asked to automate the calculation of cumulative polygon areas within a basins shapefile. The calculation will take the area of the upstream basin and add it to the area of the downstream ...
0
votes
0answers
45 views

How to scale polygon to obtain specific area in javascript?

I have got a source polygon (saved as standard js array). I want to scale it down to obtain new destination polygon in the centre with 1/3 of source area. On the cartesian space i just scaling down ...
0
votes
0answers
31 views

Clipping algorithm that can make one layer with no overlapping polygons from N polygons

I am looking for an algorithm description / pseudo code for an algorithm that can take N simple polygons and return a new set of polygons that all have been clipped such that there is no overlap in ...
1
vote
1answer
32 views

Shapefile with point or polygon

I'm just beginning with SIG and QGIS. I've been given two shapefiles with cities. One shapefile appears like point shapefile in QGIS, the other like polygon shapefile. The problem is that the ...
2
votes
1answer
93 views

Creating shapefile from polygon points for CartoDB?

I have an Excel file that contains polygon coordinates for different areas. The spreadsheet has three columns: latitude, longitude and area name. Each coordinate makes of a part of the boundary of a ...
1
vote
2answers
82 views

problem combining geometries from all features in a layer as one geometry

I am trying to combine all features of a Polygon layer in QGIS in a python plugin, and am running into this error when I try to run the combine method: "AttributeError: 'NoneType' object has no ...
1
vote
1answer
30 views

How do you create a rainbow polygon hover effect in Mapbox?

We're working on a fun website called VicePrice. It's a happy hour website using GIS instead of a list directory to show happy hour info. We've run into a snag and perhaps someone could give us their ...
2
votes
1answer
61 views

Polygons between contour lines in QGIS?

I am trying to create polygons between contour polylines within a defined area (for which i have both polygon and polyline shps) but I seem to be thwarted at every turn. Using QGIS 2.14, I am sure it ...