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

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1answer
21 views

finding the nearest point outside a series of geometries

I have db with a very large amount of geometries (circles), most of them overlapping. I'm trying to come up with a way to find the nearest point (from your current location) that is not within any of ...
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1answer
42 views

Is there a PostGIS function to get a tangent and normal line?

I'm looking for a function that will return a tangent (and normal) for a LINESTRING in PostGIS. I think this is the 3rd time I've come across the need for this function and everytime, I end porting ...
4
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1answer
176 views

How to calculate X and Y projected coordinate in batch processing

I have more than 1000 shape files (all are point features). They were initially in WGS 84. I projected them in UTM. Then through batch processing I added X, Y fields in each table. But all the X, Y ...
2
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1answer
41 views

Delete duplicate polygon nodes with PostGIS

I'm trying to delete duplicate nodes from a shapefile with QGIS, but after running the tool to delete it, nothing happens and shows the same errors. I thought that maybe importing to postgis could be ...
0
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1answer
15 views

ValueError when instantiating LineString from a mix of tuples and Point objects

I'm new to Shapely, and tried instantiating a LineString object from a mix of tuples and Point objects like this: >>> LineString([Point(1,2),(2,3),Point(3,4),(5,5)]) I get the following ...
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1answer
30 views

WKT: What is the reasoning behind the concept of a POINT EMPTY?

In data formats like WKT and WKB, we have ways of representing "empty" geometries. That all pretty much makes sense: a "LINESTRING EMPTY" is a LINESTRING type with 0 vertices. Same with a MULTIPOINT, ...
2
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1answer
60 views

Removing last point in polygon geometry using ArcPy?

This polygon was created from a grid of 500 x 500 meters, then Union, Generalize and Dissolve was used to arrive at this geometry, the laspoint not help me, I just want to have points on each vertex. ...
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3answers
52 views

How to display a table with more than one geometry column in QGIS?

In PostGIS, it is possible to use addgeometrycolumn more than once on the same table. Example: I have one table "scenes" with many attributes, and 2 geometry columns: the_geom1 and the_geom2. select ...
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1answer
40 views

Buffering a PointGeometry in arcpy only returns a line?

I am trying to buffer a PointGeometry object in arcpy to a Polygon geometry object with ArcGis 10.2. The PointGeometry object is in lat/lon WGS84 coordinates and as far as I understand, I can only ...
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1answer
35 views

Get coordinates from polygon outline with greatest distance

I'm looking into a task in ArcGIS 10.2 of which I need to discover the two points on a polygon outline where they would be at the greatest distance from each other. I have looked at ET Geowizards ...
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1answer
31 views

GeographyFromText and ST_SetSRID+ST_MakePoint different results?

Why am I getting different results? SELECT ST_DISTANCE( ST_GeographyFromText('SRID=4326;POINT(13.401111 52.383343)'), --berlin ST_GeographyFromText('SRID=4326;POINT(9.997559 53.533778)') ...
2
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1answer
32 views

Add XY Column in QGIS [duplicate]

Following on from a previous question of mine, where I was given coords in degree-mins, I have successfully converted them to decimal degrees, thanks for the help. I have created a CSV file from ...
0
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1answer
44 views

Openlayers WMS getFeatureInfo get features with geometry attribute

I am displaying map using WMSlayer and implemented WMSGetFeatureInfo control on wms layer. Tap on a location and get the features using WMS getFeatureInfo service. This service is returning me all ...
0
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1answer
44 views

PostGIS change column type varchar => geometry

I have a Postgres database with PostGIS extension on it. Also, I have a table with column lat with type (varchar 40). Column values are like this: 52.1432514 52.1431855 52.1431586 I want to convert ...
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0answers
6 views

Convert Surface to MultiSurface in SQL Server

I need to create view where geometry column is MultiSurface datatype. But, column in my table is Surface datatype. Is there any chance how to convert single Surface column to MultiSurface column ...
0
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2answers
37 views

Calculating Centroids with Zonal Geometry in ArcGIS

I have a shapefile containing polygons. Each polygon is defined by its postal code. I want to calculate the centroid of each polygon using Zonal Geometry. Sadly, for some polygons there are no ...
0
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1answer
23 views

Not empty geometry having blank text

i'm having problem with geometry column, for some rows i have geometry with blank text, this query will describe more the problem : select geom, ST_AsGeoJSON(geom), ST_Isvalid(geom), ST_IsEmpty(geom) ...
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1answer
28 views

ArcObjects - Geometry type select with Vbnet

How can I read the geometry type of shapefiles with ArcObjects and Vbnet? I want to check whether it is a point, polygon, or a line.
3
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2answers
59 views

ArcPy Data Access Insert Cursor not writing geometries to feature class?

I'm running ArcGIS 10.2.1 and am having troubles with the Insert Cursor in the arcpy module. I have an empty feature class in my geodatabase and have created the short script below to try and find the ...
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0answers
15 views

Find Coordinates of Larger Area from Sub-Areas

If I have the sets of coordinates of the borders of some sub-areas is there a way to calculate the overall border of the total area? (The coordinates are 2D Cartesian coordinates.) E.g. if I have the ...
2
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1answer
44 views

How do I use code (preferably c#) to clip all points within a shapefile that are not contained within a polygon?

So the task is simple: I want to take a point shapefile as input and remove all of the points that are not contained within a polygon. I'm using DotSpatial to do this, but the catch is that there are ...
0
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2answers
85 views

Python library or algorithm to generate arc geometry from three coordinate pairs?

I'm trying to write code to generate fixtures for a django/geodjango project. I need to generate geometry for arcs (line string) given three lat/long pairs; start of arc, end of arc and centre of arc. ...
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0answers
19 views

v.clean in QGIS Python console

I have tried to use v.clean and v.clean.advanced (by GRASS GIS) within a script in QGIS, and was not able. I followed instructions here:, but was not able to do so. I got message: "No module named ...
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0answers
27 views

USA MSA/City/County with SImplest Border in JSON

I deal with a lot of poloygon-related JSON representing US places regularly. One thing that could make reading JSON with my eyeballs easier is having a short list of US places whose borders have ...
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0answers
89 views

Invalid geometry

I'm working on some shapefiles in both ArcGIS 10.2 and QGIS 2.0. I have 3 files which I have cleaned of self intersections in ArcGIS using Repair Geometry. I have also checked for Overlaps using the ...
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0answers
42 views

How to force geometry type in (WFS) layer in QGIS

I have an external WFS source serving mixed geometry types - in other words, I have no control of the source. When adding the layer QGIS sets the geometry type to line and thus I am unable to style ...
0
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1answer
22 views

Geometry conversion problem.Data loss

I was trying to convert a roadnetwork table.Its geometry contains both MULTILINESTRING and LINESTRING.I converted all the MULTILINE string to Linestring using the query update all_india_merge set ...
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1answer
36 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: ...
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1answer
47 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
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1answer
42 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
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1answer
44 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 ...
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0answers
28 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
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1answer
92 views

using Z and M feature geometry to create line graph in 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 ...
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1answer
49 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 ?
2
votes
1answer
92 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
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3answers
34 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
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1answer
22 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 ...
0
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0answers
34 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
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1answer
60 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 ...
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1answer
61 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
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1answer
52 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
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1answer
61 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 ...
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0answers
21 views

WKBreader reuse - jts 1.9

I'm having some bad behavior reusing wkbreader. The context as of a single threaded as I use threadlocal wkbreader. I get parse exception on some geoms. When I create a new wkbreader for each ...
4
votes
2answers
288 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
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1answer
125 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 ...
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1answer
207 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
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1answer
58 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
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0answers
59 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 ...
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0answers
41 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 ...
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0answers
48 views

Detecting esri markers within certain distance using ArcGIS JavaScript API?

I have a set of coordinates that is loaded from database. I would like to detect all the loaded markers that are close to each others which is within a certain distance. so the code is something ...