(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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6
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0answers
244 views

Why do file geodatabase and SDE readers produce different fme_geometry types?

I have one very simple workbench that I am running against both SDE (9.3) and FGDB (10.0) sources. I noticed two different fme_geometry values for same type of objects. For the first one, i.e SDE ...
4
votes
0answers
437 views

What traits identify 2D, 2.5D, 3D geometries, and how can you convert downward, such as from 2.5D to 2D?

In answering this question, posed by @Burton449, I came to realize I don't have a definitive grasp on what distinguishes 2D, 2.5D, and 3D geometries. I certainly realize Z/elevation values are ...
4
votes
0answers
885 views

OpenLayers: WFS request to GeoServer to retrieve “name” & “featureNS”

Using WFSGetCapabilities I sent a GetCapabilities request to GeoServer. From the result of WFSGetCapabilities().read(), I can loop each featureType and retrieve some basic info(e.g., name, title, ...
3
votes
0answers
34 views

How do I handle heading in UTM coordinates?

In a nutshell: Given a standard (angular) GPS measurement and heading, relative geographic north. If i take my GPS coordinates and turn them into UTM coordinates, do I also have to convert my heading? ...
3
votes
0answers
348 views

C# implementation of concave hull / alpha shapes

I'm looking for a C# implementation of the Concave hull (alpha shapes) algorithm. I already found several Java, Python and C++ implementation but no C# version. The other implementation are quite ...
3
votes
0answers
141 views

What is the area that OGR extracts from the (geometry) shp files for polygons?

The ESRI July 1998 technical documentation for polygon shapefiles at page 10 makes no mention of either area measures or length measures (apart from byte/record-layout matters). Yet OGR enables me to ...
2
votes
0answers
34 views

C/C++ function to return minimum set of points required to represent a geometric shape

I am looking for a method from Grass, GEOS, or similar that will delete those points in a geometry which do not affect its shape. Example 1 +----+----+ p0 p1 p2 p1 can be deleted without ...
2
votes
0answers
50 views

Importing shapefile problem, unknown geometry type in QGIS

I have used ArcGIS extensively, but am at a new job with only access to QGIS. I am trying to import a few shapefiles and am having some problems. First, I opened the shapefiles in esris free browser, ...
2
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0answers
38 views

Geometry issues when digitising in QGIS

I'm digitising a large number of maps from hand drawn mud maps and digital images, and although I have used the snapping tools ("snap to vertex and segment", Tolerance 10 pixels, avoid intersections) ...
2
votes
0answers
34 views

how to register view geometry made by MakeLine function?

I am trying to to create a spatial view on my spatialite database. CREATE VIEW v2_pump_view AS SELECT pump.ROWID AS ROWID, pump.id AS pump_id, MakeLine( ...
2
votes
0answers
80 views

how to orthogonalize building outlines

I'm looking for a way to orthogonalize building outlines which I've extracted from a high-res DEM. I'm using the FOSS GIS stack (QGIS, GRASS, SAGA, PostgrSQL, PostGIS) and can code in Python (or ...
2
votes
0answers
71 views

Reverse parameters of a projection map

I'm user of a soaring simulator named "Condor Soaring". This simulator is at the center of a community of enthusiastic people who build sceneries (landscapes) which represents quite accurately real ...
2
votes
0answers
65 views

Needing to find parent zip code of a bunch of missing zip codes in the US

We're using MapPoint to export zip code / territory combinations. Unfortunately, the export doesn't include PO Box zip codes which mean that we're missing a lot of zip codes The PO Box zip codes are ...
2
votes
0answers
287 views

QGIS : cannot change the z-coordinate of a point shapefile using the wkb geometry format

I am using QGIS Desktop 2.5.0-Master with GDAL/OGR 1.11.0 on a windows 7. I am working on a little pyQGis script that should modify the z-coordinate of points in a vector shapefile based on a value ...
2
votes
0answers
170 views

Is there a way to eliminate duplicate 'point clusters' in SQL Server 2008 r2 spatial?

I am using the ST.Distance function to identify clusters of geometry data points. Each point has a unique reference number associated with it. I would like to eliminate duplicate clusters from the ...
2
votes
0answers
541 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 ...
2
votes
0answers
77 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 ...
2
votes
0answers
72 views

Critera for geometry or geography

What criteria do you need to take account to before you choose geometry or geography map? Is there a book or page about it?
2
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0answers
217 views

how to convert lat and longitude into distance near poles?

I am trying to convert latitude and longitude into meters in polar regions. I am looking for higher accuracy upto 0.00 meters preferably. I tried the haversine formula but it doesnt seem to be ...
2
votes
0answers
374 views

ArcGIS/arcpy: Geometry object comparison methods not working. Do they take z values into account?

I have an arcpy script that makes calculations based on an input PolygonZ feature class. What I need to do in several places in the script is test whether a point falls within a polygon in 2D. In ...
1
vote
0answers
17 views

Best SRID for worldwide data in Microsoft Sql Server geometry field?

I'm using Microsoft Sql Server 2012 to store geographical data related to hydrometeorological stations which are scattered around the globe (point layers and multipolygon layers). My data is in WGS84 ...
1
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0answers
36 views

Using arcpy.Geometry() and attribute table?

I have Polygon layer (*.shp) and I need to calculate shortest distance between every polygon's and save it into a txt file with ID (it is in attribute table) for every polygon. example of txt file - ...
1
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0answers
24 views

Split Polygon Layer by other Polygon layer in QGIS

I know there is a lot of previous posts to this subject, but I simply cannot find the solution I am after in the other posts. I have to following problem: I have two very extensive polygone layers, ...
1
vote
0answers
60 views

SQL Server Geometry draw rectangle around a line

I am VERY new to spatial data queries, so please bear with me. I have a LineString (geometry) in SQL Server and need to "draw" a rectangle around it, based on padding for the Width and the Height, ...
1
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0answers
53 views

Why is the geometry changing slightly when I import shapes into a postgresql database with postgis?

I recently posted this question when first trying to import data from a file geodatabase into a postgis database: how can I maintain curves when converting from geodatabase to postgresql using og2gui ...
1
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0answers
16 views

Quantum gis 2.2 - pasting templates

Is there a way to paste geometries in a workspace at the location i want? e.g. i want to paste a circle from another workspace in the workspace i'm working with. I need only the geometry, not the ...
1
vote
0answers
40 views

sql server geometry find points intersection buffer

How do I find the point of intersection of buffer?
1
vote
0answers
17 views

QGIS 2.0.1 Translate Feature

I have a layer containing linestrings and want to move those that are too close to each other. I seem to be missing something in the moving part though: layer = iface.activeLayer() def moveFeature ...
1
vote
0answers
18 views

WFS Updating a geometries points

I'm trying to work out on how I can insert or overwrite points that are stored in a features/ Layer? I've created a String/Text document which is already converted into GML/XML ready to be pushed to a ...
1
vote
0answers
24 views

line from min to max of a digital elevation model

I have some geometries as multipolygons and a dem (digital elevation model). I need a line from the max value to the lowest value of the dem for every multipolygon. Is qgis a tool i could use or do i ...
1
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0answers
146 views

How to determine ring orientation from lat/long coordinate points?

We have some set of point coordinates in lat/long which contribute to a polygon. From this set how do we determine the polygon is clockwise or anticlockwise?
1
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0answers
276 views

Efficient way of determining polygon intersection with bounding box

I have a set of polygons, and I need to check whether they are intersecting with a given bounding box(rectangle). What I am doing is, I am taking every vertex of polygon and checking whether it's ...
1
vote
0answers
48 views

Zonal geometry output in ArcGIS

Is there a way to specify the coordinate type in Zonal geometry output in ArcGIS? I am trying to perform zonal geometry on a raster and in the resulting output, the XCENTROID and YCENTROID are in ...
1
vote
0answers
85 views

JTS Geometry to GML3.1 encoding

I searched all the internet and I didn't find a solution to my problem. I want to convert a JTS geometry to a GML3.1 geometry. Geo tools says that have support but the have not (please check encode ...
1
vote
0answers
126 views

Inflating the boundaries created with convex hull

I have a set of lan and lat points and have plotterd a convex hull for them using QGIS. A polygon is created along the set of points and plotting them on the MAP. Now I am trying to inflate the size ...
1
vote
0answers
88 views

Assign a IGeometry to Feature.Shape

I'm trying insert a feature into a FeatureClass, but when I try to assign the geometry to featurebuffer the app return the next Error: The remote procedure call failed. (Exception from HRESULT: ...
1
vote
0answers
129 views

QGIS 2.4.0 doesn't support multiple types of geometry in GML file

I'm testing GML 3.2.1 data according to INSPIRE Data specification (version 3.0). Data for theme Cadastral Parcels shall have both polygon geometry and definition point. When I download data from my ...
1
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0answers
30 views

Buffering/extrusion of a dem surface

I have a surface representing a DEM and i would like to add it some thickness. If i simply duplicate the surface and translate it down by my thickness, i get non uniform thickness, ie thinner where ...
1
vote
0answers
68 views

Why does the postGIS file lose geometry?

I am loading shapefile data from a GPS into PostGIS via Leica ZenoOffice. This apparently imports fine with it's geometry in the attribute table. However, when I add a postGIS layer in QGIS the file ...
1
vote
0answers
136 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 ...
1
vote
0answers
368 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 ...
1
vote
0answers
191 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 ...
1
vote
0answers
58 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 ...
1
vote
0answers
85 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 ...
1
vote
0answers
211 views

Error When Generating INSERT Statements for Geometry Field SQL Server

I am populating a column of linestrings from a list of points in sql with which I use to create insert statements to populate an ID and a geometry field in a table. This creates a temporary dataset ...
1
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0answers
219 views

Inaccurate result while clipping on gis data

I am trying clip polyline data using a polygon geometry. I am using itopologicaloperator to do this task. However, resultant clipped data is off by 1 feet. Meaning that the polylines at the boundaries ...
1
vote
0answers
238 views

pgRouting results to LINESTRING geometry type

I am doing some routing queries, using pgRouting's second version of pgr_trsp function. What I can't do effectively yet is storing the results. That is, I want to able to store in a table: either ...
1
vote
0answers
37 views

PostGIS. Obtain the rotation between two equal Geometries

I've got two features with the same drawing (poliline) but one is rotated relative to the other. I would like no know in PostGIS the rotation between the two geometries to apply this rotation to a ...
1
vote
0answers
228 views

Problem import shapefile in PostGIS database

I am having a Polygon shape-file. When I try to import this shape-file in PostGIS some of the attributes in Geom Field is found empty. But in attribute table when I select that polygon It is visible ...
1
vote
0answers
103 views

Why is my linestring not valid ? was recorded from GPX file

I have a linestring that was built from points from GPX file. I've insert it to sql as geometry and when I try to run funcs on it (like STStartPoint ) I get error that line isn't valid and I need to ...