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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3
votes
1answer
72 views

Is there an alternative to the Integrate tool that will not change one of the inputs

I have two polygon layers, and would like to snap the outlines of one of them (colored poly's) to the other (grey) without changing the grey in anyway (so Integrate seems out). It should only snap if ...
1
vote
0answers
18 views

Reclassify based in neighbour polygons

I would like to do a simple operation in QGIS and I am not sure about which is the best option. I have a polygon shapefile and each one has one class attached. I want to reclassify one of them based ...
0
votes
1answer
43 views

Extracting info on polygons from underlaying raster layers

In ArcGIS 10.1, I have two layers: 1) raster of Topographic Wetness Index 2) vector layer of polygons representing soil types I am wondering how to accomplish what I am after, that is to get ...
2
votes
4answers
327 views

UK Postcode boundaries [duplicate]

Before I go and pay is there a free source for UK Postcode Boundaries, ideally down to Postcode Sector level ("AA00 0" or even better "AA00 0A")? Failing that can I generate them in QGIS if I have ...
1
vote
1answer
74 views

Smoothly interpolating Polygons from set of coordinates?

I'm still quite new to QGIS and I'm using it to display and analyze my soil data. I have point information on the distribution of the soils in a specific area and I need to create a soil map from ...
0
votes
0answers
21 views

Create indicator for inclusion/exclusion from polygon based on coordinates, and reverse

I've got a database with 570,000 or so addresses, and what is purported to be their associated Lon/Lat coordinates. However, when I compare a simple scatter plot of these to the shape of a polygon ...
4
votes
2answers
79 views

“Levelling” elevation data coinciding with polygon?

I have a shapefile containing building geometries (polygons) and a elevation dataset. The elevation data doesn't perfectly match the buildings. I want to "flatten" the elevation data so that ...
0
votes
1answer
284 views

Using the ArcGIS Runtime SDK for C# is there a method to Hit Test for a polygon on the graphics layer?

I am very new to using ArcGIS runtime SDK for C#. I have loaded a polygon from a shapefile. I wish to query if a lat/long point is inside or outside the polygon? How can I do this? Thanks in ...
2
votes
1answer
55 views

Spike finder in PostGIS

I tried to modify spikeRemover from Schmidt & Krüger. My goal it's to obtain, for each polygon, the position of the spikes. I don't need to remove it. For some reason, that I can't figure out, my ...
2
votes
2answers
266 views

Change points to polygon

I have a map which has one data point per zip code. I would like to change those points to zip code polygons. Any ideas on how to go about it?
3
votes
2answers
119 views

Can I convert the sharp edges of a polygon easily to round edges?

I use the python module "shapely" to make Polygons (like below). Can I convert the sharp edges of a polygon easily to round edges? Such that when I have unified some polygons I could issue a command ...
6
votes
1answer
546 views

Easily calculate “roundness/compactness” of a polygon

I am trying to find ways to quantitatively describe the shapes of various polygons. For my project, these polygons represent lakes, rivers, lagoons, and parks. So they can be almost any shape. One ...
0
votes
0answers
38 views

Is there a way to convert L.circle to a geodesic polygon in Leaflet

Reference: How to make a predetermined Polygon (Circle) From 4 Coordinates, The Radius and Center Longitude and Latitude in Openlayers Openlayers uses this function : createGeodesicPolygon Question: ...
0
votes
0answers
40 views

“Flood fill” polygon capture mechanisms in various GIS

Within our organisation we have a requirement to capture lines dividing land into chunks and then to create polygon features using aggregates of these divisions. In the example image below ...
1
vote
2answers
176 views

Looking for dissolve algorithm for Javascript

I have three adjacent polygons that together make up a larger shape. I need an algorithm that will dissolve the internal borders leaving only the outside border. An example would be a group of ...
2
votes
2answers
75 views

zoom over vector in leaflet

I have created a map from geojson file of administrative boundaries (polygons layer). Similar to this example. When the mouse is over the polygon feature, the cursor changes from hand to finger. In ...
2
votes
1answer
37 views

Is there a way to clip a polygon layer according to DEM elevation?

I have a polygon layer on top of a DEM. Is there a way to clip the polygon layer according to elevation, ie the clipped result being only those areas of the polygon layer between x and y altitude? ...
0
votes
1answer
74 views

Extract address data / Query point in administrative boundary

I try to create a DB in postgreSQL with all the postal adress data for a specific country. Actually I have this table full of data: id integer NOT NULL DEFAULT nextval('plz_id_seq'::regclass), ...
-1
votes
0answers
31 views

what is the math behind rasterization? Doubt [duplicate]

In Figure 4 you can see how the overlap is not complete (marked with circles). What I would like to know which algorithm that QGIS uses the rasterization? What is your standard? Is there a percentage ...
0
votes
0answers
16 views

Is it possible to add XML data as DataStore inside GeoServer?

I have multi-polygon with feature information in xml Some kind like below: <polygon> <color>red</color> <coordinates> 125.94517419942997,37.080000000100085 ...
1
vote
1answer
103 views

Get Coordinates of Voronoi Polygon Vertices [duplicate]

Is there any chance to get the exact coordinatas of the voronoi polygons? I am using Qgis software and I have the "center" (redpoint) of the polygons and I would like to export the polygons corners ...
0
votes
1answer
48 views

Query to create polygone from lines that touches in POSTGIS

I am trying to create polygons from a line layer with a spatial query in postgis the probleme is i dont have a lot of information on the lines only id of each line and geometry thanks for your help
2
votes
1answer
473 views

How do I set the fillcolor of polygons in Leaflet.js dynamically?

I'm using the interactive chloropath example for leaflet.js I figured out how to make each of my polygons add a running tally of values to the bottom of the page after each polygon is clicked. Upon ...
-1
votes
1answer
55 views

Determining if polygon contains point to populate point's field with polygon's name using arcpy.da?

Am trying to check if the points in a point shapefile are contained within a polygon shapefile and if so, to populate a field in the point shapefile with the name of the polygon and to populate the ...
8
votes
3answers
2k views

Using polygons to apply unique value to all raster cells within those polygons?

In ArcGIS 9.3, I have a raster file that I would like to "mask" with polygons, giving a single value to all the raster cells that overlap the polygons. How can I do this? Here's a screen shot, ...
0
votes
2answers
46 views

mapbasic, create polygon, insert node

Hi I try to create a parsel table from coordinates. My scripts are below. Why it does not show the results on the map? Thank you in advance! Create Table "parsel" (Parsel_Adi Char(10)) file ...
1
vote
1answer
70 views

How to close spaces within a polygon in QGIS 2.2?

I have a shapefile displaying the borders of several city units. One of its polygons, however, had free space consisting of four vertices in it. I created another polygon inside the free space and ...
0
votes
1answer
64 views

How to add point attributes to containing polygon?

I have three layers in a QGIS project: layer 1 is a boundary layer of polygons each with and id I will call "p_id" layer 2 is a point layer each with an id called "p_id" layer 3 is a .csv layer ...
0
votes
1answer
39 views

How to select a specific area (in a polygon form) determined by some value range in a raster band?

For example, I want create a vector layer with polygons that represents all areas where the elevation is between 500 and 600. Someone has any idea to help me? I'm using PyQgis 2.2.
11
votes
5answers
4k views

How best to fix a non-noded intersection problem in PostGIS?

I'm using a PL/R function and PostGIS to generate voronoi polygons around a set of points. The function that I am using is defined here. When I use this function on a particular dataset I get the ...
0
votes
1answer
61 views

QGIS convert polyline to fixed width polygon

I have a shp file of polylines for trails, and I need to convert them all to be polygons that are 8 ft wide (4 ft from the center of each side of the polyline). I tried a following a few other posts ...
3
votes
1answer
1k views

Problems converting polygon to point [closed]

I'm trying to convert polygons to points with ArcGIS 10. My polygon layer has 2 attributes that I want to give to my point layer. I'm using the Feature to Point function from the Arctoolbox, but it ...
0
votes
0answers
50 views

Draw polygon shape via Qbutton

Ideally; a Ui Qbutton is needed that will activate map canvas editing to add a polygon via the classic mouse click rubber band method. Upon a concluding right click with the active tool, editing ...
3
votes
2answers
102 views

Double (triple, quadruple) size of polygon using ArcGIS for Desktop?

I have several polygons, measured in acres. I'm looking to double the area, either by a buffer, or some other method. I will need to triple and quadruple in the end, as well. I have tried to use ...
0
votes
0answers
22 views

Error while importing data from GSHHS_f to MySQL database

I'm doing a summer project on geospatial development using python and I've been following the book Geospatial Development Using Python by Packt Publishing. The thing is, I've tried to import the GSHHS ...
1
vote
1answer
48 views

Rectangle polygon is displayed as triangle

i am wondering why a rectangle polygon that i have created on an official german surveying website (downloaded as compressed shape in a zip-file) is displayed as a triangle when loaded in qgis. mighty ...
2
votes
1answer
133 views

How to surround a Polygon object with a corridor of specified width?

I'd like to build a corridor surrounding a polygon, so that the corridor's outer bounds all have the same distance to the inner bounds. Like this: I've made this lousy graphic in Paint, since I ...
0
votes
0answers
41 views

QGIS Intersecting polygons

I have two different shapefiles, each with polygons for one country. I want to find out which polygons of one shapefile are part of the polygons in the other shapefile. For example Polygon 1 of ...
1
vote
0answers
41 views

Authoring map with advanced gradient symbol for ArcGIS web service?

I need to prepare a web service which will display the gradient of polygon points values. It has to look just like in this picture: link to the picture (please ignore the arrows). Each polygon is ...
3
votes
1answer
75 views

FME: Using WorkspaceRunner to batch 2 readers

I need a little help using the WorkspaceRunner in FME. Essentially I want to batch run polygon shapefiles in one folder (30 of them) against another load of files, in the form of a tiled grid (26 ...
0
votes
2answers
92 views

I have a table with a series of lat/long points - how do I convert them into polygons?

I have an Excel sheet with about 150 points (lat and long in decimal degrees) which belong to about 15 different polygons. The columns I have are FID, NAME (the same between polygons), POINTS (points ...
0
votes
2answers
58 views

Joining two polygon layers based on distance?

I'm new to GIS so this question may be an obvious one. I have one polygon layer of urban land use and another polygon layer of swamps. How do I join the two layers so that I get a column in the ...
0
votes
0answers
49 views

Determine the list of circles (from 100K circles), that overlap with a given polygon

This question was asked on StackOverflow, came here because no response has been posted so far. Existing data structure we have polygons represented as an ordered list of lat/long coordinates and ...
8
votes
1answer
995 views

Splitting landcover polygons (parcels) into equal sizes, while retaining road access for all?

I would like to split landcover polygons which surround a road polygon into equal sizes, while ALL resulting polygons should have access to the road! Is there any chance to do this automatically? ...
0
votes
1answer
98 views

Setting a value on a raster where a polygon intersects cells

I reviewed all of the supposed 'answers' and I just do not see that they really answer my question. Mostly because the ones I'm reading are setting values either inside or outside a boundary. So let ...
1
vote
1answer
64 views

How to compare multiple spatial point patterns over a polygon

I have multiple point pattern distributions over the same region/polygon. Each point pattern distribution has different number of points. Here is an example of two spatial point patterns for the ...
1
vote
1answer
137 views

Intersect between polygonal shapefiles error

I'm encountering a problem when I try to intersect two different shapefiles. They are all new shapefiles I created to descibe the land cover and the land use of a city. The problem occurs when I ...
0
votes
1answer
36 views

Find extent of data inside many polygons

This is similar to Calculate polygon area inside extent I have a few different polygon datasets which describe things like soil type, bushfire risk etc. For each property boundary we want to see how ...
0
votes
0answers
81 views

How to split an oblong, irregular polygon layer into even pieces?

I have a polygon layer (landuse) that I want to split into 100 meter pieces. The polygons show landuse along a road. I want to split the polygons layer so that I can then calculate the percentage of ...
4
votes
2answers
465 views

How to Polygonize a polyline shapefile in QGIS 2.2?

When I used QGIS 1.8, I was able to transform polyline layers to polygon layers with the Polygonizer plugin. In QGIS 2.2, this function has been subsumed into the Processing toolbox. Unfortunately, ...