Tagged Questions

5
votes
0answers
81 views

How to find the maximum-area-rectangle inside a convex polygon?

In this post we are looking for algorithms / ideas on how to find the maximum-area-rectangle inside a convex polygon. In the following figure, numbers are the areas of the fitted rectangles. As shown ...
6
votes
3answers
226 views

What geometric attributes do polygons possess, and how can these be used to filter features?

Given a polygon featureclass containing many polygons of different sizes and shapes, which geometric attributes (area, perimeter, etc) could be used to filter the polygons? It's probably best to ask ...
9
votes
1answer
348 views

Self intersections for polygons, howto solve?

I have a question about repairing a self intersecting polygon shapefile. I have a shapefile containing Polygons (ZM) which has self intersecting features. If I use the "repair Geometry" tool, it finds ...
5
votes
1answer
127 views

How can I increase performance on inserting features with polygon geometry?

I have a problem when inserting features with polygon feature class in FGDB. This is my code: ... initialising some fields (does not affect performance) m_featureBuffer.Shape = ...
0
votes
0answers
17 views

World country borders in polygon geometry format [duplicate]

Possible Duplicate: Where do I get territories data? Is there some source I can get all world countries polygon geometry points with latitude and longitude? I find it for USA states but ...
0
votes
2answers
390 views

How can I convert Polygon to LinearRing Geometry?

How can one convert a Polygon to LinearRing geometry using OpenLayers? I'm thinking that I can do this by getting bounds of the polygon, then use this to construct a Points array. Finally, use ...
0
votes
2answers
670 views

Calculating shape perimeter/area per zone in ArcGis 10

How can I calculate geometrical features of polygon (perimeter and area) per zone (similar to zonal stats for rasters)? I have a square fishnet (approx 20x35, 1 square kilometer each) and I need to ...
3
votes
1answer
665 views

Postgis - Converting 'geometry_dump' data type to a 'geometry' type

I am working with a dataset of property boundaries that has had ST_Union() run on it, thus all the polygons appear as a multi polygon in one row of a table. I would like to separate these out so I get ...
2
votes
1answer
671 views

How to make a predetermined Polygon (Circle) From 4 Coordinates, The Radius and Center Longitude and Latitude in Openlayers

I know how to make a predetermined Polygon in Openlayers (see below). Please have a look at http://studio.netnrg.co.za/dev/rnd/blake.loizides/openlayers var feature2 = new ...
2
votes
1answer
849 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 ...
8
votes
3answers
6k 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 ...
1
vote
0answers
237 views

export topology tables to txt files using arcobjects, generating directed graph , finding intersections

I want to export topology tables to text files: for points: 1 id x y for lines: line id fompoint.x from point.y topoint.x topoint.y for polygons: id line id 1, line id 2... 2 arc ...
14
votes
2answers
2k views

How can I find a point inside a polygon in PostGIS?

How can I find a point that is guaranteed to be within a given polygon in PostGIS? I am aware of the ST_Centroid function. However, the centroid is not always within a polygon, see below: ...