(1) abstract geometry; (2) storing geographic data in projected coordinates; (3) a generic ESRI term for vector features; a class for "geometry" objects.

learn more… | top users | synonyms

1
vote
1answer
99 views

Test for polygon orientation

I'm want to merge multiple geometries with Geotools (starting off with one geometry) but the result is a polygon that has a clockwise orientation. This gives a invalid geometry. My code for the merge: ...
3
votes
1answer
584 views

How to get the width and height of a rectangular polygon in PostGIS

I have a table with point features saved in the my PostgreSQL database, and I can run the following query to get the extent of the point features and I turned the extent back into a geometry: SELECT ...
0
votes
1answer
308 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'. ...
0
votes
1answer
328 views

How can I get the circle of a sphere (on Earth ellipsoid) around a point using the Latitude and Longitude?

Specifically finding points along the circle. If possible without converting into Northing/Easting beforehand. I'm looking for the fastest possible way to calculate points in Latitude/Longitude in a ...
4
votes
1answer
228 views

How to offset/displace overlapping lines in a web map?

I have a dataset of points representing a To/From status - something like distribution centres and delivery addresses. When the user clicks on a point I'd like to show the relationships between this ...
0
votes
1answer
422 views

Using Z and M feature geometry to create line graph in ArcPy/Python?

I am a Python (v2.6.5) noob trying to plot a series of 3D polylines into graphs. So far I've come up with: # Import system modules import arcpy, os, sys, string from arcpy import env ...
0
votes
1answer
161 views

Geometry to Shapefile

From importing the shapefile to postgis, its geometry is added to the database postgresql. The question, how can I load the shapefile in the Visual Basic.Net using the geometry in the database ?
4
votes
1answer
2k views

Radius of curvature for curves in road segments for entire road network

I have a road network shapefile for a US state and I am trying to derive the radius of curvature for road segments in this shapefile. I need to be able to perform this task within just a few functions ...
1
vote
3answers
45 views

Adding combined footage to points from the beginning of a line

I'm trying to add the footage of each point from the beginning of the line to the end. There are around 4k vertexes between the two ends that I need to put the footage from the beginning of the line ...
0
votes
1answer
25 views

How to check VALUES from different datasets spatially near with ArcGIS10

I need some suggestions, let's see: I have two heavy polyline datasets, from different sources, so they will never be coincident (it doesn't matter this issue). Both have the same field from which I ...
1
vote
0answers
245 views

SetSpatialFilter worked unexpected when using ogr by python

I am using ogr python binding to read the shapfile, this is the code: ..... bbox="POLYGON ((20.18164062 30.63867188,20.63867188 30.63867188,20.63867188 30.18164062,20.18164062 30.18164062,20.18164062 ...
0
votes
1answer
274 views

file formats to represent georeferenced 3D data

I am looking for an overview of file formats that can store geo-referenced 3D geometries. There are no further requirements such as texture support, etc. I have found the following formats so far and ...
1
vote
1answer
215 views

Locating 0-points multipart polygons using arcpy

By Running this piece of code: import arcpy arcpy.env.workspace = "C:\working\GEODATABASES\\tests.gdb" fcList = arcpy.ListFeatureClasses() for fc in fcList: with arcpy.da.SearchCursor(fc, ...
0
votes
1answer
273 views

How can envelope angle be calculated?

Azure SQL has a hemisphere limitation where it errors on any geography having an envelope angle greater than 90 degrees. My coworker wants to set up some detection in the web server to catch such ...
1
vote
1answer
234 views

Replace Polygon geometry in SDE Database using FME

I'm still trying to wrap my head around using FME and encountering another issue. This is my scenario: I have a master SDE database that i am trying to update using the data from a GDB file. I was ...
5
votes
2answers
2k views

Multilateration Code

I am currently writing some code to do multilateration using TDOA and currently struggling and wondering if anyone has any reference code that can be used as a test case with some sample data that I ...
0
votes
1answer
960 views

SQL Geometry Query similar to Select by Centroid

Does anyone know if it's possible to query SQL geometry by something like 'centroid of polygon'...similar to ArcMap's select by location? I'm using SQL Server 2008 R2 as the DBMS. I have two polygon ...
3
votes
1answer
2k views

Is it possible to get a binary geometry from PostGIS?

PostgreSQL (via C# Npgsql driver) returns geometry column (PostGIS) like a hex string (EWKB as I understand) for this query: SELECT ST_Transform(geometry, 4326) FROM myGeometries; Result (for ...
1
vote
1answer
117 views

How to identify and highlight invalid geometries?

I'm am trying to clean/edit shape files that were created by algorithm in Qgis. My problem is when I try to split some polygons,they have invalid geometry. Is a way to identify these error maybe in a ...
0
votes
0answers
215 views

Prevent self-intersecting loops when exporting polygon layer from ArcSDE to File Geodatabase?

I am using ArcGIS 10.1. The source data is housed in an ArcSDE instance that does not allow self-intersections. When I export this data to a file geodatabase and run check geometry ...
1
vote
0answers
62 views

PostGIS automatically creating geometries after importing using QGIS DB Manager

I have a shapefile consisting of linestrings, in which some of the features have null geometry. Yet, after importing it to PostGIS, using QGIS' DB Manager, a geometry is created for those features ...
3
votes
2answers
151 views

How do you determine how straight a LineString is? [duplicate]

I have a bunch of LINESTRINGs and need to classify them based on how strait they are. My idea is to compare the length of the LINESTRING to the distance between the first and last POINTs. I'm ...
2
votes
3answers
98 views

ogr: what is the advantage of using `geom.Clone()` over `geom`?

What is the advantage of using geom.Clone() over geom? Simple example: geom = link_feat.GetGeometryRef() newfeature.SetGeometry(geom.Clone()) # or newfeature.SetGeometry(geom) ...
2
votes
2answers
1k views

How to split circles in 8 quadrants

I am using ArcGis 9.3 and I need to split a large number of circles in quadrants. The circles corresponde to a 200m buffer of a point layer and, for each point, I need to split the buffer in 8 ...
3
votes
1answer
222 views

Getting geometry of drawing in ArcGIS Server JavaScript API

To me, ArcGIS Help and Online Resources is always full of unneccessay information and missing some important points. For example there are lots of samples for drawing but I couldn't find any thing for ...
2
votes
1answer
127 views

Decimal Degree data erases itself between edit sessions in QGIS

I have a shapefile with point data. I calculate the $x and $y of the points successfully I save the changes and close the edit session. Once I reopen the attribute table, the data after the decimal ...
6
votes
1answer
624 views

Configuring Geoserver to use a specific postgis geometry column as the default

I have a PostGIS table with two geometry columns, both multipolygon but one with SRID 4326, the other 3857. When publishing the table in Geoserver, I realize that Geoserver defaults to using the first ...
0
votes
1answer
42 views

Postgis add Geography to function()?

i was wondering im getting different results when using geography() on different positions within a query. So, whats the most accurate way of forcing geography() over a functions with geometry ...
2
votes
0answers
78 views

PostGIS does not export shortest path to Shapefile

I am trying to draw a bunch of lines overlaying the globe map in a WGS84 projection. To this effect I have created a PostGIS DB with a table that has one column containing linestring data. My problem ...
1
vote
2answers
130 views

How to disable “Simplify geometry” via Python?

After I've loaded a layer from a table in my db I'd like to disable the 'Simplify geometry' (found in Layers/Properties/Rendering) programatically using Python. I've tried several versions of ...
1
vote
0answers
87 views

Merging parcels but keeping Geometry seperate

I am working on updating a parcel layer we received for a project, and I have duplicate parcelID's for parcels and I have been merging these to create 1 parcel as to not have duplicate ID's. My ...
4
votes
3answers
3k views

converting/parsing geojson into com.vividsolutions.jts geometry

Does any has any experience with converting string geojson into com.vividsolutions.jts geometry object (point, polygon, etc). Maybe there is some java library I cannot find. Greets!
1
vote
2answers
103 views

How can i change the geometry of an existing layer?

I work with Qgis, v. 2.0.1. I have a point layer in which I have structures that could be represented as lines or polygons, but at the moment they are represented as a group of points. I know I can ...
1
vote
3answers
232 views

Geometry vs geography for line-to-polygon intersection

I have two WGS84 NAD83 shapefiles, one polygonal, the other containing lines: Geometry: Polygon Feature Count: 1294 Extent: (-79.761059, 44.991143) - (-57.105486, 62.582865) Layer SRS WKT: ...
1
vote
3answers
219 views

Invalid geometry message when using Difference tool

I am using the Vector \ Geoprocessing \ Difference tool to get the resulting area when taking a) current ground disturbance away from b) historic total ground disturbance to give c) what has been ...
0
votes
0answers
28 views

Quickest method for determining which postcode is 2 miles north of original postcode? [duplicate]

What is the Quickest method for determining which postcode is 2 miles north of original postcode? For instant L17. I know how to determine the distance between 2 points as below, but the above ...
0
votes
1answer
47 views

Hard to get my head around, generating average price for houses in each quadrant

I'm able to determine the average price of houses sold in a particular area (like the squares on image below) dependent upon postcode. Although I can generate the average sale price for a particular ...
1
vote
2answers
872 views

Is there an average size for British postcodes?

Is there an average size for British postcodes? Or a method of determining the size for a particular British postcode? Thanks. Considering creating a related program and this would be valuable ...
0
votes
0answers
51 views

Speed drastically reduced when including geometry, is there a way to improve?

-- EDIT: Issue is that the shape files being used are at too small of a precision and way too large, output was 488M total, looking for different source -- I'm having some speed issues with a complex ...
2
votes
1answer
341 views

QGIS 2.2 rendering problems

i have a problem with some geometry. When i run the check geometry validity i get an error coming back that the rings are not closed, so recangular forms that i have surveyed are showing up as ...
4
votes
4answers
488 views

How to determine if an object is a circle

I have a polygon shapefile that consists of many different shaped features. I would like to identify only those shapes that are circles. Is there a way to do this? Is it a calculation I could do in ...
0
votes
1answer
156 views

Getting wrong value for area of geometry using Spatialite?

I am trying to implement a measuring tool on apple maps for IPAD. As a part of that i collect all the touch points on the map into an array and constructing a geometry object from that and then ...
1
vote
1answer
153 views

How do I convert OS coordinates (X and Y) to longitude and latitude coordinates?

How do I convert OS coordinates (X and Y) - Eastings and Northings to longitude and latitude coordinates? For example X and Y below X (Eastings): 347904 Y (Northings): 287484
1
vote
1answer
251 views

How do I figure out the grid references (Eastings and Northings) necessary to create a circular 1 mile radius around one location?

How do I figure out the grid references necessary to create a circular 1 mile radius around one location? For instance: Grid Reference: SO 47904 87484 X (Eastings): 347904 Y (Northings): 287484 ...
3
votes
1answer
393 views

How do I figure out the longitude and latitude coordinates necessary to create a circular 1 mile radius around one location?

How do I figure out the longitude and latitude coordinates necessary to create a circular 1 mile radius around one location? I don't mind how many coordinates that takes. For instance: Latitude = ...
0
votes
1answer
370 views

Get the vertices on a LineString either side of a point (Sql Server 2008)

I have a point that sits on top of a LineString, both Sql Geometry types. POINT('0.5 0.5') LINESTRING('0 0 NULL 1, 1 1 NULL 1') I want to find the vertices of the LineString that lie either side ...
1
vote
1answer
287 views

Using M 'Measure' value in SQL Server 2008

MS Sql Server 2008 geometry type supports adding Z and M values to geometry objects, including linestrings. However, I cannot find any way to make use of these values, since methods such as ...
7
votes
1answer
4k views

How to draw polygons from the python console?

I've been visiting and revisiting the page on geometry handling in the PyQGIS Cookbook: https://www.qgis.org/en/docs/pyqgis_developer_cookbook/geometry.html but can't seem to figure out how to get the ...
3
votes
1answer
421 views

Get geometry column back when counting points in polygon using PostGIS

I have two PostGIS tables: earthquakes and borders, which contain point data on earthquake locations, and polygons of countries in the world respectively. I want to try and count the earthquakes ...
1
vote
1answer
121 views

Adding geometry to rows with missing X,Y inArcGIS

I have a table with X, Y data that contains many rows with still missing coordinates. Now I would like to edit it in ArcGIS 10 and simply add the geometry for selected lines after identifying the ...