Process of creating geometric polygon features.

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8
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6answers
2k views

How to split a polygon into quadrants?

I have a Alberta province (Canada) section polygon shapefile in GCS_NAD83 with 255,000 polygons. I like to split each section into 4 equal quadrants (NW, NE, SW, SE) The Alberta province has ...
2
votes
0answers
34 views

How to split a polygon into quadrants in R/Qgis?

I am solving the same problem as How to split a polygon into quadrants?, except that I am looking for a solution in R or QGis. So I have a polygon layer shapefile, which is unfortunatelly not exactly ...
0
votes
2answers
45 views

way/tool to automatically generate polygons on map knowing polygon width and height and spacing

I need to create a large number of polygons (say 1000) on a georeferenced mosaic (from aerial photographies). I know polygons' height and width, and I know the spacing between them. I can also provide ...
1
vote
0answers
21 views

Creating polygon with attributes using ArcGIS Desktop? [closed]

I'm new of the use of arcGIS. I have xy data that descibe a polygon. But when I use the tool "point to line" I lost all attributes. There is a way to create a polygon with attributes. I try to explain ...
1
vote
1answer
32 views

Defining polygons based on thickness maps using ArcGIS for Desktop?

I want to find and create polygons that demarcates three different inflection points in a thickness raster: where the thickness start to increase, where the thickness is at its max and where it starts ...
0
votes
0answers
56 views

Dividing a polygon into certain areas (open source solution preferred)

I have a polygon with an area of 50.000m². Now i want to devide this area in two polygons of different areas with a line layer. The left polygon should have an area of 30.000m² and the right polygon ...
1
vote
1answer
93 views

Generate territory polygon from sets of points

I'm looking for a simple way to generate contiguous "territories" from sets of points. Say, points A, B and C are in territory 1, and D, E and F are in territory 2, then generate polygons that lie ...
4
votes
3answers
2k views

Creating collection of polygons from collection of points?

I have a set of points, which are spread over a wide geographical area. I need to be able to create a set of polygons which best represent the clustered points. In parts, some points may simply lie ...
1
vote
0answers
28 views

Geoserver does not render polygon properly

I am trying to a get polygon layer from CSV file. I chose to do it via rasterization and polygonization in QGIS, howerver, Geoserver has problems to correctly render some polygons. This is how the ...
1
vote
0answers
28 views

Network Analyst Add City Boundary as Polygon Restriction

I have a network I am trying to create but am finding the service area polygon I create are "leaking" outside of the city boundary. I was curious if there was a way to add the polygon as a restriction ...
1
vote
0answers
34 views

How to find the the boundary co-ordinates from a given set of coordiantes? [duplicate]

How to find the the boundary co-ordinates from a given set of co-ordiantes? I understand that this question asked previously and answered here How to find the boundary co-ordinates from a given set ...
2
votes
2answers
52 views

QGIS - Create equal length polygon along polyline

How can I create a series of polygons along a line? I need to assess the density of a number of targets along a line within a corridor. I have tried the following: creating a buffer, using the ...
4
votes
2answers
111 views

Best way to get a bounding polygon of all features in a file .gdb

I have an arcpy script that dynamically creates a filegeodatabase and its featureclasses from uploaded spatial data, currently point and line features and possibly polygons in the future. I am ...
12
votes
5answers
8k views

How do I create a convex hull in ArcGIS Desktop?

I would like to be able to create a convex hull in ArcGIS Desktop 9.x, but I cannot find an appropriate tool. How does one go about creating one? I am interested in answers for all license levels: ...
2
votes
2answers
101 views

Can't transform lines to polygons

I have a similar question to: How to join lines in QGIS for later using "lines to poly"? I have a line shapefile that I wish to transform into a polygon shapefile. After making some ...
11
votes
6answers
3k views

How to find the boundary co-ordinates from a given set of co-ordinates

Given a set of coordinates, How do we find the boundary coordinates. <== Figure 1 Given the coordinates in the above set, How can I get the coordinates on the red boundary. Boundary is the polygon ...
7
votes
2answers
366 views

How to extract vectors from map using QGIS?

I am trying to extract building footprints from a raster map (as shown in the example below). Please note that the maps are out of copyright, have been scanned and georectified by a library and have ...
2
votes
0answers
76 views

How to extract polygons from a road network?

I need to extract faces (or polygons) from my road network and calculate their areas. I mainly use Arcpy packages but even if you know it in QGIS APIs, I'd appreciate if you'd share it with me. If it ...
5
votes
1answer
183 views

How to grow several concave hulls until they completely fill a larger area without overlap?

This is my problem: I have a very large point layer with polling station locations across one country; each point belongs to a specific constituency (900k points, 4k constituencies). I wish to use ...
2
votes
1answer
130 views

Polygon Between Contour Line

I have a contour generated from SRTM, How to fill the space between that contour with polygon (for all part) but it generates field in attribute table automaticaly, example in image above between ...
3
votes
2answers
1k views

Colouring areas between (vector) contours?

Is it possible to colour areas between (vector) contours without making it a DEM first? Joshdoe seems to have done so in Create filled contour map with GRASS but does not say how.
1
vote
2answers
71 views

Creating counties in QGIS

I have a raster map (a photocopy I took from an Atlas), and a vector map of the UK. The raster map shows pre-1890 Scottish county borders. I have geocoded the map so that the raster borders overlap ...
2
votes
2answers
1k views

ArcGIS: Create polygon using file containing point coordinates

I have a text file containing the projected coordinates of the points that define a single polygon. The X, Y coordinates are separated by Tab Is there a tool in ArcGIS similar to "Add X,Y Data" in ...
1
vote
3answers
102 views

How can I insert a bounding box or polygon in a PostGIS geometry field?

I have a field in my table called 'geometry' that was created thus: CREATE TABLE "public"."sites" ( "id" int8 DEFAULT nextval('sites_id_seq' :: regclass) NOT NULL, #... A few MORE fields ...
0
votes
1answer
178 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 ...
2
votes
0answers
63 views

Weird-looking France after OSM import with osm2pgsql

After importing france-latest.osm from Geofabrik, using osm2pgsql, it seems that the polygon attributed to Metropolitan France (osm_id = 1403916) is a bit odd: I'm far to be a geography expert, but ...
1
vote
1answer
83 views

Dynamically drawing a polygon around another shapefile, ArcGIS 10.2

Let's say I have a vegetation raster that indicates the density of forest all over the world. I also have a shapefile that contains the admin boundaries of each country in the world. The easy part is ...
1
vote
1answer
55 views

Raster domain output polygon has is an empty feature class. Shape_Length and Shape_Area = 0

I am trying to convert a 32-bit floating point raster with 205289 columns and 120615 rows to a polygon using Raster Domain. It creates a feature class that does not contain any polygon. There is a ...
5
votes
3answers
1k views

How to find line length in QGIS while editing?

I am using QGIS (before, I used ArcView). I would like to know if there is any way during the editing phase of a vector (line or polygon) to know the length of the line (total and partial) that is ...
1
vote
1answer
39 views

Creating contiguous / adjacent ellipses

I've only just started using drawing tools in ArcGIS, and have the following question I haven't found the answer to online. Is there a way of taking a drawn ellipse (at a slight angle) and adding say ...
0
votes
1answer
49 views

Adding custom shapes to a new shapefile

I am using ArcGIS 10.1 and I drew a rectangular shape to designate a junction on a map and i would like to add that to a new shapefile. Could you please give me some ideas.
1
vote
1answer
87 views

Distance analysis of 3-D surface in ArcGIS using VB.NET

Using VB.NET I created a 3D polygon in ArcGIS to model a fault plane and now I want to find two different distances from a point on earth's surface. How to go about this? Can some one help with the ...
0
votes
1answer
74 views

Difference between 'point' and 'WKSpoint' in ArcGIS

I have to add 3-D points to make a polygon in ArcGIS using VB.NET. I have defined an IpointCollection and want to add points to this. I have options to add 'point' or 'pointcollection' or 'WKSpointz'. ...
3
votes
3answers
489 views

What Is The Ideal Workflow To Map (British) Postcode Territories

I'm looking for the best workflow for mapping postcodes and calculated territories, but being relatively new to mapping I'm struggling on a few details and also the best practices for displaying these ...
0
votes
0answers
50 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 ...
0
votes
2answers
101 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 ...
1
vote
1answer
766 views

How to create a polygon feature class from polylines in Python Arcgis?

I am trying to create a polygon from polylines. I've created this script but it gives errors of Arrays. Thanks. import arcpy polyline=r'C:\temp\temp_lines.shp' ...
0
votes
2answers
217 views

creating isochrones in postgis/osm2po/pgrouting and then saving the isochrones as polygons

So I am creating some isochrones in pgrouting based upon a table from osm2po. Now I have a query that will get all of the edges that are c driving distance away from a point. My question is, how can I ...
0
votes
0answers
15 views

creating Polygon from LineString and a width

I have to create a Polygon from a lineString and a width. Ex: Given a street as a lineString (Or a list of points) and a width, create the polygon (the road). I am using Geotools, but I couldn't find ...
0
votes
2answers
211 views

How to create polygons from unclosed polylines?

I have a layer of driveway that is in polylines unclosed . They are just two parallel lines outlining the width of the driveway. Then again, there is a gap (sidewalk layer) and driveway continues ...
8
votes
3answers
719 views

How to apply the four colors theorem in a polygon map in ArcGIS/ArcToolBox automatcally?

I need to apply the four colors theorem in a polygonal shape in a way that I do not need to choose manually each color to put in each region. I wish to knows if there is any extension, plug-in, script ...
16
votes
1answer
5k views

How to divide a polygon into specific sizes using ArcGIS?

I have several thousand irregularly shaped polygons in a shapefile. I want to be able to split each polygon into three areas, and to specify what the size of those areas (they sum to the previous ...
2
votes
1answer
248 views

Convert SpatialGridDataFrame in to polygon shapefile in R

I have a SpatialGridDataFrame in R and want to plot just one of its attributes as as polygons in a GIS. There seems to be no simple way to do this. The situation is complicated by the fact that the ...
0
votes
2answers
117 views

How to generate polygons upto the edge of other polygons?

I am doing some work on a pipe network (blue lines) and I am trying to attribute the information about the street to the pipes. I have 2 polygon layers one of the blocks (green hatch) and one of ...
1
vote
2answers
200 views

How can I group Points to make polygon via Python

I have an array of coordinates Point= [lat,long] ListPoint= [[38.203655,-76.113281],[38.10,-76.12],..] I wanna make a polygon that contains all these points ? There is a project developed by ...
1
vote
1answer
4k views

How to create a circle with specific radius? [duplicate]

Possible Duplicate: Conflicting measurement units with buffer ftools I have a shapefile as input. How could I create a circle with a radius of exactly 500 meters, using QGIS?
1
vote
1answer
147 views

How to create polygons from a polyline graticule?

I'd like to make a polygon shapefile out of a polyline shapefile showing a graticule. However, using the "Line to Polygon" tool results in a peculiar...something: Other standard tools like ...
1
vote
1answer
251 views

Python: Ray-trace a WGS84 point with heading and distance

One of my services defines geofences for a mobile app. The geofences consists of a lat/lon pair and radius in meters, in JSON, e.g.: { "geofenceId":"geofence_b39da38cff7be4b4693cbc31b2394bbb", ...
14
votes
3answers
2k views

Producing building shadows?

How would you generate building shadows from building footprints? I have attribute values for the heights of buildings. So would preferably like to have the shadows' sizes vary based on that. The best ...
2
votes
1answer
952 views

how to connect points to create a polygon boundary in QGIS

I have 31 points in a shapefile, which delimit a field (it's an irregular shape). I want to connect those points so they create the boundary of a polygon. Does anybody know a kind of "connect the ...