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
911 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 ...
2
votes
2answers
217 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?
2
votes
5answers
865 views

Counting road intersections and blocks

I have a shp file that consists of the road system of Mexico City. I would like to count the number of road intersections (crossings) and blocks (which I would define as a segment starting from one ...
2
votes
3answers
294 views

Is it possible to make a routable graph from Polygons?

I would like to know if it is possible to make a graph with pgrouting 1.05 on polygons. What I mean is that I have to make a graph on a database without roads but with polygon geometry. I would like ...
2
votes
4answers
216 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 ...
2
votes
2answers
64 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
3answers
177 views

Merge 30000 polygon shapefiiles in a logical manner in ArcGIS model Builder

I have 30000 shapefiles (a1.shp to a30000.shp). They are all polygons. Each polygons has one and only one polygon feature in it. I need to Merge the polygons into 1000 shapefiles. My output would be ...
2
votes
1answer
78 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
2answers
1k views

how trace polyline between two points?(Esri)

How i can draw a line between two points...e.g.: I have initial point and endpoint and i need trace a line between this points...how i can do that?
2
votes
2answers
452 views

Polygon country boundaries in decimal degrees

Using Google Maps, I'd like to create draggable polygons (on the fly) of country boundaries (they don't need to be particularly precise). Something similar to this, but for countries. So I want the ...
2
votes
2answers
881 views

Assign unique ID to each polygon

I feel like this should be really simple and I am missing something. All I wish to do is assign a unique ID to each polygon since I have multiple identical FID values. In MS excel I would simply type ...
2
votes
1answer
1k views

How to get the radius of a “circle” in Openlayers

How do you get the radius of a circle in openlayers? I have searched quite a bit and cannot find any resource for this. please help. Here is my code but I want the radius or circumference of the ...
2
votes
1answer
1k views

Transform polygon to equivalent circle, QGis

I have a polygon and I'd like to find the radius of an equivalent circle from a particular point within the polygon. The polygon would have a large (infinite) number of points evenly distributed ...
2
votes
3answers
485 views

Clip a raster using a shapefile into multiple rasters?

I have a raster file representing a large area and a shapefile of 30 polygons representing watersheds. I would like to clip the raster with the shapefile to create 30 rasters representing each ...
2
votes
2answers
236 views

Finding points along a path

I am unsure of the best approach to this problem. I can think of some ways of doing it which I will list below but I am looking for the best and most efficient way of doing this. Problem Given a ...
2
votes
3answers
794 views

Zonal Statistics as table creates output but some are Null

Here is my newest issue: I have temperature as a raster file and different ecoregions of a province as polygons. What I want to do is calculate the mean temperature per ecoregion. I succeeded in ...
2
votes
2answers
47 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 ...
2
votes
2answers
53 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 ...
2
votes
1answer
123 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 ...
2
votes
1answer
34 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 ...
2
votes
2answers
179 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?
2
votes
3answers
168 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 ...
2
votes
3answers
157 views

How to remove vertices or lines within a polygon?

I have transformed a *.dxf-file into a polygon shape-file. In many of the polygons i have lines whicht do not belong there but i can not delete them as i normally delete vertices on polygons by ...
2
votes
1answer
375 views

combine raster and polygon values in R

My question is similar to this one Get Raster Values from a Polygon Overlay in Opensource GIS Solutions but I think I need another step. I have a polygon layer of ecoregions which I brought into R ...
2
votes
1answer
2k views

How to combine (join?) two overlapping polygons to determine combined area they cover?

How do I combine (join?) two overlapping polygons to determine the combined area they cover in ArcGIS 10? I am sure the Geoprocessing tools can do it, but just how eludes me.
2
votes
3answers
170 views

How to minimize the number of nodes in a polygon?

I'm building a web application that will be transferring polygons from server to client. Initially, the shapefile is coming from an external source that I have no control over. Often, I find polygons ...
2
votes
2answers
863 views

How to create a multipart polygon?

I have two polygons that consist of two separate polygons/lines in QGIS). How can I make this into a multipart polygon, which consists of 1 line in QGIS?
2
votes
2answers
361 views

count features in polygon shapefile A that fall within each feature of polygon shapefile B

I have two polygon shapefiles, each of which contain multiple (possibly overlapping) polygons. Is there some way, using GRASS, to calculate the number of polygons belonging to shapefile A that fall ...
2
votes
2answers
482 views

FME Donut Hole Extractor

I am using FME to fill in some small holes within polygons. I have used DonutHoleExtractor to split these out, however I have found the output via the HOLE port also brings existing 'filled' holes ...
2
votes
1answer
2k views

How to set polygon opacity on openlayers?

I have some prolems showing polygons in openlayer. I want to divide one city in areas. For the moment I have zona1 and zona2. I took lat and long from google maps so I think they are correct. My ...
2
votes
1answer
147 views

How to digitize from a map with additional detail views?

I have a map with a river that includes islands within it. Some islands have a blown up version (detail views) outside of the river showing land ownership details. I would like to make polygons ...
2
votes
2answers
2k views

How to automate point-in-polygon queries in ArcView?

Layer1 = point shapefile (multiple points, geocoded) Layer2 = polygon (1 attribute; (1,2,3...)) I want a non-gis person to be able input a single address and be told the attribute of the polygon ...
2
votes
1answer
103 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 ...
2
votes
3answers
157 views

How to generate dartboard shapefiles using ArcGIS for Desktop?

I am rather new to ArcGIS and I have a simple question regarding a problem I cannot fathom. I am attempting to generate a polygon 'dartboard' shapefile. Radially, there should be a circle from 0 to ...
2
votes
1answer
366 views

Distance of points in polygon to nearest polygon edge

I have a polygon shapefile with about a dozen polygons (Area.shp). I have an equation that calculates a value for points (or small areas) as a function of distance to the edge of these polygons. I ...
2
votes
2answers
635 views

Percentage of polygon in one shapefile within polygon of another

I'm a newbie, apologies if this is obvious/has already been asked and answered but I couldn't find anything. I have two shapefiles: 1. an administrative boundary layer for a county in the UK known as ...
2
votes
1answer
272 views

How to perform a cascaded combine from python script in QGIS?

I'm working with a large dataset, and I need to be able to combine up to 400,000 polygons. I have been using the QgsGeometry::combine(QgsGeometry* geometry) function and simply looping over all ...
2
votes
2answers
167 views

How can a style be set on a specific polygon using OpenLayers?

Using a polygon id, I want to highlight a polygon, while the mouse is outside of the map area. I can identify the polygon using the following approach: x = 53; for(i=0; ...
2
votes
2answers
389 views

Creating Long & Lat for Polygons

I have a base map image with micro regions, however in the attribute table there is no information regarding the long & lat. Is there a way I can create a long & lat for each micro region? ...
2
votes
1answer
958 views

Identify duplicate polygons to enable removal after reviewing attributes

I wish to label overlapping polygons so that I can manually locate each overlap then review the attributes of each overlapping polygon and decide which suite of attributes to maintain before ...
2
votes
1answer
482 views

How can I get the corners of a polygon in latitude and longitude?

How can I get the corners of a polygon -a square/rectangle, to be precise- in latitude-longitude format by using its geom value -or some other way, perhaps-? Thanks.
2
votes
2answers
425 views

Selecting Part of a Polygon

I have a dataset, in shapefile format, for agricultural land grades in England. It is divided into 7 categories in its attribute table. As the file is a large file and I only want a small section I ...
2
votes
3answers
278 views

How to calculate exact area of a loaded jpg map in to arcmap?

I calculated the polygon area through arcmap.but i'm not sure that the area is not actual,may be scale is not right. so how to calculate the exact area of a jpg image?
2
votes
1answer
147 views

Merge section polygons in PLSS

I am trying to merge quarter quarter sections of polygons from PLSS into a quarter section. However, I also want it assigned to correct Township/Range/Section while merging. I know I can hand merge ...
2
votes
3answers
539 views

Split polygon with holes to get several hole-less polygons

Unlike this thread I actually need to split the polygons into several hole-less polygons. I'm not sure on how to approach to this problem. I have polygons with holes of many diferent shapes, like ...
2
votes
1answer
373 views

How to display only one pie chart for polygon features in QGIS?

I'm working with Qgis on a project and I have a small problem. I have to do some demographic research and therefore I have a .shp file from a given country with 10 districts for example. Now, I know ...
2
votes
3answers
911 views

Accessing coordinates of polygon

I have designed a polygon in a web page and the coordinates are stored in the database of the type polygon. However when I check the database, I find GEOMETRY - 120B under polygon field. What does ...
2
votes
1answer
581 views

How do I subdivide and edit polygons preserving topology?

I'm using QGIS. I have a layer made up of many adjacent polygons - let's call them "countries". I currently use the Atlas plugin to export each "country" polygon to a .png file. I want to further ...
2
votes
3answers
2k views

Openlayers get coordinates from polygon

please could someone help me and bless me with an example of how to get coordinates from a polygon in OpenLayers?
2
votes
1answer
426 views

SUM Area irregular polygons per grid cell

I have a shapefile of irregular polygons and a GRID (both as raster and polygon grid). How can I count the AREA SUM of irregular polygons per grid cell? Can use ArcGIS, QGIS or R. (Application: ...