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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27 views

Polylines and polygons - QGIS-2.14.3-1

After extracting contour lines from a DEM (obtaining polylines), and transforming them to polygons, I export the vector layer with polygons to a DXF. Then I import the DXF into Corel Draw to manage ...
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13 views

Drawing line and finding bearing using ArcGIS for Desktop?

I need to draw a line from a point within a polygon to the edge of said polygon. I do not need to know the length of the line, only the bearing (in degrees) for the line. We are using ArcMap 10.3.1
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21 views

Generate points layer at line intersection

I have a line layer that is actually buffer polygons converted to a line layer. I would like to generate points at all places where 3 or more lines intersect. I would settle for places where 2 or more ...
3
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2answers
94 views

Creating OUTSIDE_ONLY buffer around polygon using R?

I would like to create buffers in polygons, surrounding my original polygon. However, I want to keep only the "outside polygon", not include also original polygon. In Buffer in ArcGIS I can just set ...
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1answer
40 views

Colour specific polygons on a postcode map - QGIS

I am working on a UK postcode map. It only has the first bit of the postcode, e.g. BR12. I have an excel spreadsheet with the longitude/latitude of specific points as well as their postcodes. Instead ...
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1answer
26 views

Combining Data from raster and polygon

I am teaching myself GIS at the moment, and there are still some matters I haven't quite got the hang of. I'm using ArcGIS 10.1, and have three datasets: LAYER 1: A population dataset at a high ...
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1answer
30 views

ST_Union or ST_Collect on PostgreSQL union result?

Newbie to PostGIS/Postgres. I have the follow query which returns me 2 GEOMETRYCOLLECTIONS. Is there a way within my current query to return one polygon? SELECT ...
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0answers
20 views

QGIS - convert multiple polygons to evenly spaced points within polygon boundary

I need to convert the polygons in a vector layer to evenly spaced points within the polygon boundaries in QGIS. The vector file contains >1000 polygons mostly with overlaps. The attribute data of ...
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2answers
45 views

Calculating relative share of area covered by water/percentage of polygon area that overlaps in ArcGIS for Desktop?

I need to calculate the share of the area within a 50km radius of major German city centers that is covered by water with either Arcmap 10.3.1 or Qgis 2.14. My plan is to use the Global Lakes and ...
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0answers
41 views

Creating voronoi polygons from polygons?

I have a database with buildings and for some further analysis I need to: aggregate adjacent buildings (preferably without losing the height attribute, but I can work my way around that) once I have ...
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0answers
29 views

Algorithm to simplify a Polygon/Series of Points to a given number of Points

I have a polygon (or let's call it just a series of points). I want to simplify it (reduce the amount of points) to a given number of points. Currently I use Douglas Peucker and try to guess the ...
1
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1answer
36 views

QGIS 2.81. Why can i only see my whole polygon and nothing if i zoom in

I have a polygon layer with one object. It is a flood inundation map. I could see my layer all the time in every scale factor. From one moment to the other it changed and know it is only visible if i ...
3
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1answer
41 views

How can I merge two adjacent polygons which borders are not touching each other

I want to merge adjacent single polygons which are apart from each other. Important note: I cannot use ArcGIS, I need to do this programatically, in any language (R, Python, Ruby, PostGIS) doesn't ...
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0answers
57 views

How can I fix Russian border polygon?

is there easy way to fix Russian border polygon in CartoDB? The polygon is given by CartoDB. From the picture you can see that the polygon covers also Estonian territory. But I need to make there (on ...
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0answers
17 views

QGIS-I have 37 polygons, can I bulk create 2 other sets of 37 that are 1 px larger all the way round and 1px smaller

I have 37 polygons covering a Lakes spatial extent at a particular point in time. I need to bulk create 2 sets of polygons. One 1 px larger all the way around and one 1px smaller to calculate the area ...
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2answers
50 views

How can I build a grid of equal square polygons in ArcGIS 10?

Not having them depend on decimal degrees, but on a certain distance. When I use a tool it asks me the length of the cell in degrees, but I want all sides of every cell to be equal and with degrees ...
1
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1answer
20 views

How to auto Correct Polygons that are not drawn correctly?

I was part of a project recently where handheld GPSs were used to collect vertices of parcels. After plotting the points using 'P2One' plugin in QGIS I found out that some of the polygons were twisted ...
2
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1answer
20 views

Help getting polygons out of multi-polygon GeoJSON files

Farmer here. Very new to GIS. I am trying to load shapefiles or KML files to an online site/service called FarmLogs.com. Once my "fields" are uploaded the site can tell me the amount of rainfall ...
3
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0answers
35 views

Find Distance Between Two Polygons

Given two polygons (point, line, or up to 8 vertices) I need to be able to calculate the shortest distance between them via code I write or a call to an API (I haven't been able to find one that does ...
6
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2answers
136 views

How to calculate how many polygons I can put inside a polygon?

I usually use qgis. I explain my problem with an example: there is a forest (irregular geometry1 ) and one tree (geomery2). I want to know the maximum number of trees that the forest can contain. ...
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0answers
9 views

MSL/AGL bounds checking in PostGIS for Line/Polygon Intersection

I have a table with Polygons and columns defining an optional upper and lower altitudes bounds and altitude type. The Type can be MSL, AGL, or NULL, if unbounded, and can be set separately for upper ...
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20 views

scale polygon in Qgis [duplicate]

The task is to scale a polygon in QGIS. The procedure is performed tracing the polygon and then apply a scaling factor ( the factor used is " Distance on the ground" / " Distance on map " ) . Both ...
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0answers
9 views

Allocating premises between postcode polygons and telephone exchange area polygons in QGIS?

I have telephone exchange areas as one polygon layer and postcode (codepoint) polygons as another. The postcode polygons have the number of premises in each postcode as a field. I want to estimate the ...
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1answer
49 views

Inverted lat lon on drawn polygons in Openlayers 3

I am working on a map in openlayers 3 with geoserver I display the layers as WFS and I added the draw and modify interactions, but when I save the drawn polygons the coordinates of the newly drawn ...
5
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3answers
148 views

Smoothing method for big polygons

I'm looking for an alternative to 'snakes method' for smoothing very big polygons, which I created from SRTM elevation datasets. The problem is that the smoothing is getting stuck after a while with ...
3
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2answers
55 views

PostGIS - Get a point inside a line or polygon

I need to get the center point of a line or polygon to make marker for my app. So that when you click a marker the geometry appears (line or polygon). I used ST_Centroid to make it work. The result ...
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0answers
18 views

SRIDs do not match for the two geometries in oracle spatial

I am trying to resolve where some points from Point Geometry lying outside the Polygon geometry. I want to filter those points which are lying outside the polygon geometry. I am getting error where ...
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0answers
29 views

Polygons created with R are corrupted when imported into ArcMAP

I created some polygons using R and to get a better visualization and some other stuff I need to import those into ArcMap. However, when I imported the polygons I realized there are some holes in some ...
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1answer
37 views

Google Earth: Circular polygons that follow earth curvature

I'd like to draw filled circles in Google Earth which follow the curvature of the earth, i.e. for 1000ft altitude, not only the circle's edge but also the center is required to be 1000ft above ...
3
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0answers
48 views

Emulating Polygon Neighbors tool in ArcGIS Desktop 10.0? [duplicate]

I'm using ArcGIS 10.0 SP5. Have a set of 4000 polygons (featureclass A) and I'd like to summarise the values of the polygons (featureclass B) which touch the boundaries of these polygons (ie. those ...
0
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0answers
14 views

Why do area calculations of OSM polygon shapefiles return negative values in ArcMap?

Whenever I tried to calculate the area of polygon shapefiles (OSM, Geofabrik) part of the polygons have negative values. All values appear to be right except the fact that around half of them are ...
0
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1answer
19 views

Cut Tool or Process to mimic cutting in a “cookie cutter” like fashion

Say I have a sidewalk polygon, and on that segment of sidewalk I have 5 tree grates that I want to cut out of the sidewalk polygon. Is there a tool or an easy process that I could cut out one tree ...
0
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1answer
18 views

Triangulation method to create multipatch objects (decomposition of polygon surfaces)

Which triangulation method or algorithm does arcscene use to create multipatch parts (patches) as you see in the attaching picture. The algorith decompose the polygon area into a set of triangles ...
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0answers
14 views

Loading Data into Vector Layer Polygon

My first layer is a map. My second layer consists of points: bars with GPS coordinates (.cvs file). My third layer consists polygons, creating different area's for the bars. So, the points of the ...
2
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0answers
22 views

PyQGIS: intersection of one node layer with two polygon layers

I´m new with the use of PyQGIS and I´m working in a problem applied to a water supply systems modelling, where I need to distribute the water demand in about 5000 nodes (network junctions). I´m ...
2
votes
1answer
39 views

How can I calculate the percent of a raster cell covered by a polygon?

First, I am going to try and intersect a raster and a polygon shapefile. I'm not 100% sure how to do this (or if I need to do this for the next step), so if you have any suggestions please let me ...
2
votes
2answers
52 views

OpenLayers 3 / Cesium polygon projection issue

I am using OpenLayers 3 and Cesium (via ol3-cesium). I have created a few rectangles (using a MultiPolygon) stacked on top of each other. Whereas in OpenLayers the rendering (left) is as expected, ...
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1answer
33 views

How to calculate distance from point to nearest polygoin via road network (polyline) ARCMap 10.3.1

Using ArcMap, is it possible calculate distance from a postcode (point) to nearest polygon using a road network layer (polyline)? As opposed to just calculating Euclidean distance?
3
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0answers
38 views

Can I reorder the points in a GEOS LineString?

Using libgeos, when I buffer() a polygon and then getExteriorRing() [to make a slightly smaller outline copy of the polygon just inside the original], it seems that which point on the new geometry is ...
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0answers
16 views

Why does connected polyline (KML file) appear unconnect in arcmap as layer?

I created polygone in google earth and imported it to arcmap as layer. All things are OK but when I converted polygon to polyline, there some parts of polyline has not shown although its vertices ...
0
votes
0answers
21 views

OpenLayer WMS Polygon Fill color dynamically

i am new to OpenLayer Geoserver and PostGIS. I want to color my WMS Polygon Layer which has multiple polygon in different color based on some value. Is this possible with wms or wfs. Color for polygon ...
1
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1answer
23 views

Storing GML Polygon in PostGIS 2, ERROR: unknown spatial reference system

I am receiving GML as part of a larger XML message. When I receive the XML it is unmarshalled to Java objects. I have no rights to alter the schemas or the generated Java code. Therefore, I later have ...
0
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1answer
22 views

Finding neighbors for non adjacent polygons in R [closed]

I'm looking for a method or function in r-project that create a neighborhood matrix from a group of polygons that don't touch each other, like polygons of set of blocks separated by streets in a town. ...
2
votes
0answers
24 views

How do I merge a point attribute table to a polygon attribute table in QGIS or GRASS?

I have a point layer containing the following data: I want the following polygon areas to be added to the point attribute table as all the points occur inside the various features of the polygon ...
2
votes
2answers
112 views

What is the difference between Polygon To Line and Feature To Line in ArcGIS?

What is the difference between Polygon To Line and Feature To Line in ArcGIS? Is feature to line a more abstract way such that it takes in not only polygon but like dots and other feature classes ...
1
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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
votes
1answer
38 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
votes
2answers
76 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
votes
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
votes
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 ...