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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2
votes
1answer
42 views

Compute the area of a given polygon (in vector format) lying between specified lines of latitude

I have species distributions (in vector format) and I would like to calculate how much of the area for a given species distribution is within certain lines of latitude, such as temperate and tropic ...
0
votes
1answer
240 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
193 views

Search for geojson polygon in mongodb implementing a custom vector tileserver

I am building a vector tileserver in node.js using mongo 2.4.7 as database. My database contains geojson data from multiple sources and they are in many layers. It is important to render the layers ...
1
vote
2answers
54 views

adjusting polygons to boundary and filling holes

here's the problem: Where: 1: department boundary 3: polygons inside department boundary that "touch" the department boundary(1). They are not necesary fitting well inside 2: holes between 1 and ...
1
vote
1answer
1k views

Control view of Multi polygon in Google map

We have multipolygon WKT. We have no issue to draw all of them in Google map. Below are the codes. The only issue is that we want only the first polygon to be visible but the rest to transparent. How ...
1
vote
1answer
30 views

Calculating distance between borders when one polygon inside another polygon?

I am brand new to ArcGIS and having some trouble. I would like to calculate the distances between the border of one polygon to another polygon. However, these polygons overlap. Thus when I use the ...
11
votes
3answers
1k views

Self intersections for polygons, how to solve?

I have a question about repairing a self intersecting polygon shapefile. I have a shapefile containing Polygons (ZM) which have self intersecting features. If I use the "repair geometry" tool, it ...
0
votes
2answers
41 views

How to select and shade polygons I am interested based on existing shape file in Arcgis 10.2

The shape file already includes polygons I am interested and others. I want to make a map put in my paper showing which regions in the world I am interested. Thanks.
2
votes
1answer
28 views

How to dissolve geodatabase map across two subdivision levels in Arcgis 10.2

The existing polygon database contains attribute table with the following structure, and has three levels; country, state, and city (and many other countries not listed below). I want to dissolve the ...
0
votes
0answers
39 views

How to generate random GeoJSON polygons (latitude, longitude)

I am looking how to generate polygons in GeoJSON format with random locations (latitude, longitude), if I generate totally random set of points it will not produce valid polygons. So my question is ...
4
votes
1answer
120 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 ...
0
votes
2answers
404 views

How to get WKT or GEOJson by country or city name with Overpass API?

I'm trying to understand Overpass API, I'm experimenting with it, but cannot get what I expect. Overpass API doesn't return me neither polygon shapes, nor WKT, nor GEOJson, nor even a highlight of the ...
0
votes
1answer
18 views

CartoDB simple process

I'm attempting to create a simple process with CartoDB, I have a layer with number of polygons, I want to to run a SQL with a multipoint line to report which polygons were intersected.
0
votes
2answers
62 views

Simplify Multigeometry polygons in QGIS

I am really new to QGIS and KML so this might be obvious but I am too ignorant to know what to do. I have some KML files I would like to use in an application but they are much more complicated than ...
2
votes
2answers
99 views

How to convert a shapefile to a grid file

I was wondering whether anyone might be able to tell me in layman's terms how to convert a polygon layer to a Grid file in ArcGIS 10.1 or ArcGIS 10.2?
0
votes
0answers
17 views

save polygon from image to PostGIS database

I'm working on a software to detect buildings from satellite imagery. so far I have managed to separate the building with other objects of the image. My problem now is how to save every building in ...
2
votes
2answers
103 views

Convert surveyor's calls in excel table to polygon shapefile

Do you know of a way to take surveyor's calls from an excel file (for example: N35-45-15W 60.0 ft, etc) and have them generate polygon shapefiles point by point in GIS? I know you can easily do this ...
0
votes
1answer
87 views

CartoDB.js - Accessing table fields in hover function

I am new to CartoDB.js and javascript in general, and I am attempting to highlight polygons in response to a mouse hover. My plan of attack attempts to utilize one of the interesting templates ...
1
vote
1answer
151 views

JTS Polygon simplification without holes

I have a set of polygons without holes. I wish to merge any intersecting polygons. I don't want to have any holes in my simplified polygons. Is there a recommended way to achieve this using JTS? The ...
0
votes
0answers
22 views

QGis Filtering postgis layer with boundbox

I know It is possible to split a polygon feature by interactively drawing a line over it in QGIS 2.0 with the Split Feature command.The issue i have is that postgis layer i am trying to work on is ...
4
votes
1answer
772 views

Problems converting polygon to point

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 ...
2
votes
2answers
509 views

How to divide a polygon with another polygon

I am working in ARCMAP 10. I am trying to divide a polygon with another polygon. I don´t want to clip any part away, but only divide the polygon? The polygons are stored in two different layers. ...
8
votes
5answers
3k 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 ...
3
votes
1answer
56 views

PostGIS - when I add a polygon, delete overlapping areas in other layers

I'm starting to work with PostGIS and I'd like to solve the following problem: In my database, I have multiple land use class layers, for example: "residential", "industrial", "commercial". The ...
0
votes
0answers
34 views

Why does it take so long to run zonal statistics?

QGIS 2.0 Windows 7 I have pulled agricultural data from NASS CDL in tiff format. I want to track where a certain crop has grown over the years. My intention was to use a county shapefile overlaid ...
2
votes
1answer
48 views

Area of polygon split by a line

I need a query that return the area of two polygons that have been split by a line. This is what I did so far: SELECT ST_Area(ST_Split(surface.geom, limite_a.geom)) from surface, limite_a where ...
2
votes
1answer
36 views

Calculate the number of points in a freehand polygon ArcGis Javascript API

I'm drawing a free hand polygon on my map. Now I want to calculate the number of points found in that polygon. I have done this code, which my now is giving me the number of points found in the map ...
0
votes
0answers
21 views

Splitting polygon layer and joining attributes

I have two shape layers -- one a layer of counties in Florida and another a layer of MSAs in Florida. I would like to generate a new layer that has the following properties: MSAs that overlap more ...
2
votes
1answer
59 views

Batch create fishnet using FME

I want to create a fishnet based on the extent of individual polygons from a list of polygons. I plan on processing each resulting fishnets further. I am maintaining a worldwide data set on Quarter ...
1
vote
1answer
57 views

How do I add coordinates to a polygon layer to be able to sort the polygons from north to south in QGIS?

I have a polygon file, where each polygon represents one property. I want to be able to sort the polygons from north to south or vice versa. I need them to be sorted in this way when I export them to ...
0
votes
1answer
37 views

Numbering rows and columns in polygon grid (fishnet)

I seem to be a bit stuck on what i thought would be quite straightforward. I've created a fishnet of polygons, all 25 x 25 metres, 100 polygons by 100 polygons. My main task is to create a ...
2
votes
1answer
62 views

How can I filling ring in QGIS 2.2?

I created a polygon which covers a park. But I want to distinguish some small buildings located inside the park. Consequently, I want to distinguish them and use them as independent patches inside the ...
1
vote
3answers
104 views

How combine different geometry types into the same feature class

I've searched the question in this blog. Maybe I don't use the right words but anyway my problem is not present in any post so I'll try to explain my question by opening a new one. I have a polygon ...
0
votes
0answers
15 views

GRASS GIS - v.select- ERROR: bad allocation -

I'm quite new to Grass GIS. I have two vector maps, one of a grid (each grid cell is a polygon) and one of a much larger polygon. I've been trying to select the grid cells that lie completely within ...
8
votes
7answers
9k views

Get boundary of raster image as polygon in ArcGIS 10

I have a rectangular raster image in ArcGIS. My question is: how can I produce a polygon which is just the extent of the raster image? That is, I want to have a polygon layer with a single ...
1
vote
1answer
100 views

How to extracting raster data to multiple polygons?

I have a reclassified raster dataset (10 classes) and I want to find out the area of each class contained within multiple (hundreds-to-thousands) polygons. I have all the polygons in the same ...
13
votes
6answers
6k views

How to use ST_Intersection?

Here's a quick summary about what I'm trying to do: I have 3 tables in Postgres, 'a' and 'b', each have a Polygon column, and 'c' has a Point column. What I'm trying to do here is to get the ...
3
votes
1answer
56 views

T-shaped polygons

Is there any coefficient that can indicate T-shaped polygons ? Examples of T-shaped polygons :
0
votes
1answer
45 views

Using polygon layers to cut holes in other layers

I have a number of polygons in a layer (old rehabilitation areas) and want to be able to selectively bring one to top and use this to cut a hole in the others and fill this with the cutting polygon ...
0
votes
1answer
22 views

Non-deletion of nodes in QGIS

I've come across an annoying irritation. I have a .SHP converted from MapInfo which consists of a large number of features, a lot of which are made up of a whole heap of combined/multipart polygons. ...
0
votes
1answer
32 views

Get all points with in some range of a point (or range of point)

I have got a list of points and a fixed range (10m). So what I have to do is for each point I have to find all the points present in a table with the 10m range of the given point. For example: Let ...
1
vote
1answer
46 views

Identify geographic location to points

I am quite new in QGIS and I really need your help. I have a map of Kenya divided into 68 districts and I have coordinates of 30.000 schools. The points have one variable besides the latitude and ...
0
votes
1answer
47 views

How to select/create polygons of interest based on existing polygon database and indicate other polygons that share boundaries in ArcGIS 10.2

The existing polygon database contains attribute table with the following structure, and has three levels; country, state, and city. I am interested in the state of 'Anhui' for example (and many ...
0
votes
0answers
20 views

QGis 2.0.1 (german version): Transect with square polygons

I would like to create with QGis 2.0.1 ( Dufour , german version) several square polygons (1km ²) that seamlessly connect to each other, so that a strip ( transect ) of 9km times 1km length results . ...
5
votes
2answers
128 views

How to calculate the area between two line shapes?

I'm a newbie using QGIS (2.0). I'm trying to calculate the sidewalk area of a city. For that I have some shapes, extracted from Mricostation, with the topology (facades, fords, fences, etc.), but ...
2
votes
1answer
153 views

how to create an outline polygon (footprint) from raster data with postgis?

how can I create a polygon, containing the actual outlines (aka footprint) of a raster file with postgis? I just need the outlines of the data containing parts of the raster. ST_PixelAsPolygon ...
9
votes
3answers
11k views

How to convert .shp to .csv including attributes AND geometry?

I have a .shp file with 60k+ entries, all of which are polygons with corresponding attributes (acreage totals, landowner names, tax ID #s, etc.). What I ultimately need is a .csv file with all of ...
0
votes
2answers
34 views

Polygon Data to Fit Raster

I'm working with an NHD Flowline of streams and rivers in NC, and I'm trying to only retain the ones in the raster. I tried to convert to the raster to a polygon and was going to clip them, but in the ...
0
votes
0answers
25 views

Intersecting Overlapping Polygons Individually in ArcGIS

Map Layers: -Census Tract Shape File w/Population Data -Set of Store Locations with 5 Mile Buffers (Significant Overlap Between Buffers) I have create feature layers for both and I am trying to ...
10
votes
3answers
4k views

How to merge two 'incompatible' polygon layers in ArcGIS?

I have two layers of polygons with administrative boundaries. Although they come from the same data provider, they seem to have small discrepancies and do not 'fit' each other. How could I merge ...