Questions tagged [gml]
Geography Markup Language (GML) is an OGC Standard for expressing geographical features.
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Using ogr2ogr to convert GML to shapefile in Python?
I am trying to convert a GML to an ESRI shapefile using ogr2ogr utility in a python script.
I have successfully installed the GDAL/OGR package via osgeo but I am now struggling to find/understand ...
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What's an efficient way of detecting road junctions on a map? [closed]
I may receive maps from any source for my project, and for the C++ algorithm I'm making, it's imperative for the algorithm to know where road junctions (nodes where more than two road segments meet) ...
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Remove unneeded columns from geographic data file?
I have some GML data that has some unneeded columns in it. I'd like to remove these columns in order to reduce the file size. (To clarify: I mean that the file has many points in it, and each of these ...
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GML, KML, GeoJSON - Speed rendering 3109 polygons?
I am working with Geoserver, serving U.S. Lower 48 counties to openlayers (3109 polygons - lots more vertices). The counties are loaded into a postgis database. I am curious about developer ...
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Is srsName of "EPSG:4326" spec compliant in GML 3.1 / 3.2?
I sometimes see srsName="EPSG:4326" in GML documents (e.g. https://postgis.net/docs/ST_GeomFromGML.html, although my particular source is not public). The intent (except perhaps for axis order that ...
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Convert GML to GeoJSON
I have downloaded a GML file from Statistics Canada and would like to convert it into GeoJSON to use parts of it in a D3 visualization on the web. However, I did not find a converter that would do ...
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Why does one part of GML -> KML conversion not work on Google Maps?
I have a client who wants to visualise cancer incidence and mortality rates by local/unitary authority across Great Britain. I've used Ordnance Survey data to get the boundaries of the authorities in ...
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Why can't I edit KML/GML layers?
Newbie here confused by my first experience in QGIS
I have a handful of lines defining a bike route.
Originally they were saved in a .gml file and later translated into .kml so they could be viewed ...
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3
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What does it mean "GML is an XML grammar"?
I'm trying to get my head around the theoretical side of XML and GML. The OGC web page for GML states that:
The Geography Markup Language (GML) is an XML grammar for expressing
geographical ...
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How to write GML with Geotools?
I'd like to write GML using Geotools. Unfortunately, I can't find documentation on a GML Writer (except for this one from 2006: http://docs.codehaus.org/display/GEOTOOLS/WFS+++GML+DataStore).
Could ...
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Storing GML surface in PostGIS
I'm using PostGIS 2.0.0 and would like to store a GML Surface in a way that allows calculating intersections between that surface and various points and lines. In my case, the Surface will have one ...
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How to convert GML Surface to SHP Using OGR?
I have a very large .gml file with multiple layers in it. I would like to export one of these layers to .shp. It is a polygon layer (of lakes). However, I am getting the error:
ERROR 1: ...
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How to import/export geographic information (gml or csv file) to geodatabase?
I am searching for C#/Java libraries that can import and export geographic information (gml/csv file formats) from and to geodatabases.
If not yet available, is there other way to do this task?
Any ...
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Linux Tool to visualize CityGML file
Can you recommend a Linux program that allows me to visualize CityGML models (3D)?
I have tried a whole bunch so far (most of them via wine but also native ones) but I couldn't get a single one of ...
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Getting OS Mastermap data into QGIS?
I have been tasked with getting OS Mastermap topography data into QGIS system to compliment our other map layers. The data comes in .gz format. Which I am told needs to be decompressed before I can do ...
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Advantages either way between GML and Shapefiles? [closed]
After a good start many months ago of getting into GIS through QGIS, I had to drop what I was doing and did not touch it for quite some time. I am now able to get back into it and have a need to load ...
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Is GeoJSON an OGC format
I am using geometries in a JavaScript page and it is best to use JSON objects rather than GML which is XML based. I heard of GeoJSON, but is it an OGC open format?
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Seeking Tutorials for GML?
Do you know any good tutorials or any resources for learning from the beginning GML?
I am asking because (later) i would like to learn how to make a application schemas in context of INSPIRE.
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What is the best way to convert WKT String to GML String
What is the best way to programmatically convert WKT String to GML String? Every reasonable library (at best available in some Maven repository) can be used.
Till now I came up with this solution ...
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Converting GML to Geodatabase Feature Classes?
I have a series of XML files containing GML tags such as :
<gml:posList srsDimension="2">454780.3125 525867.9375 454762.0625 525994.5625
and I need to convert these into ESRI feature classes.
...
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Looking for web and desktop tools with GML support
I am a graduate student and a novice in GIS field. I have few GML files that contain vector polygon data and I want to see them in a map format. The problem is that I do not have access to ArcGIS/...
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Using Python to parse an XML containing GML tags
I am trying to write a python script which pulls GML tags out of an XML file and formats them into WKT for inserting into a PostGIS database. I have been successful in doing so for an XML containing a ...
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Is there an XML equivalent to GeoJSON?
In my web application, I am retrieving geospatial data from a server backend (Java) to the browser frontend (JavaScript). I am considering two options of how to serialize the data in this ...
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WFS Request Layer (GML) with Filter
Is there a solution to request the GML layer from Geoserver with filter like using bbox:
http://localhost:8080/geoserver/tiger/ows?service=WFS&version=1.0.0
&request=GetFeature&typeName=...
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Why are the polygons in my GML not rendered?
I tried to view GML files from download services ( http://services.cuzk.cz/gml/inspire/cp/epsg-5514/ ) and I have a problem with viewing of polygons from layer "CP:CadastralParcel". This Layer ...
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Which topology file formats are supported by QGIS?
I would like to know which topology file formats are supported by QGIS.
I am particularly interested in displaying topologies encoded with TopoJSON or GML. But any other portable topology file ...
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Experience with Geoserver's GML Extension
I'd like to know if Geoserver's GML extension works (well) with GeoServer 2.1-RC2 and whether it will enable uploading of GML files via REST API.
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Adding GML files in GeoServer?
How can I add GML files to a GeoServer 2.2.2 instance?
How can I edit them "on the fly" and save the results back to the server using OpenLayers?
I'm adding a vector layer. in which we want to use ...
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How to convert WFS request to GML?
I have the following:
var popProto = new OpenLayers.Protocol.WFS({
url: WFS_HOST,
version: "1.1.0",
featureType: layerName,
featureNS: namespace,
srsName: "EPSG:4326",
...
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1
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How to get a GML overlay on Google Maps?
Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me.
A bit of ...
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How to set up Geoserver app-schema feature chaining?
I am using Geoserver 2.12 with the application schema plugin to map a PostGIS database schema to the GeodesyML schema. I need to set up a WFS request that returns GeodesyML output such as:
<wfs:...
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Selecting certain text from attribute values in QGIS using field calculator
I am using QGIS 3.16 (Field Calculator). I have a number of values in the attributes of my GML file that read:
'Nonconiferous Trees' or
'Nonconiferous Trees (Scattered)' or
'Nonconiferous Trees, ...
4
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1
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What is the best format to encode polygons such as lakes?
I am looking for a standard format to encode polygons, such as lakes, in one file that is easy to create and common so that others can use it in different GIS systems. Every file will contain data on ...
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2
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Modelling per-segment attributes in GML LineString
This is not a software-specific question, but rather a question about how to represent some concepts in a GML LineString.
It has to be GML, for policy reasons.
Consider a GML LineString consisting ...
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1
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GeoServer DescribeFeatureType response missing attribute for GML only
We have a GeoServer 2.18.2 instance serving data from PostGIS that seems to return a different structure for DescribeFeatureType requests depending on the outputFormat specified in the request.
One of ...
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Is it valid GML if the boundary of a polygon intersects itself?
Is it valid GML if the boundary of a polygon intersects itself?
E.g. I have this polygon consisting of some gml:LineStingSegment and one gml:Arc:
My task is to import GML based data (german ALKIS ...
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Is it possible to convert a .shp file to .gml?
Is it possible to convert a shapefile to a gml file?
If so, how and using what tools?
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Using ogr2ogr to convert multiple GML files to a postgis table
I have a folder with 150 .gml (addressbase) files I need to upload to my postGIS/postgres database. After the first gml is uploaded, the rest will be appended to it to form a single table. However I ...
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How to convert gml:pos to latitude and longitude?
I'm trying to figure out the latitude and longitude of rail stations that are contained in this WMS feature list. I'm completely new to the GIS field, so please forgive me if I use the wrong terms ...
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Using zoo-project WPS service in QGIS WPS-Client
I've created a python wps service in the zoo-project framework, which is used to calculate a Line of Sight based in on a start point, an end point and a start point height. The service works fine if i ...
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How to use the OGR/GDAL configure options in QGIS Python environment
I'm looking for a solution how to use the OGR/GDAL configure options (--config) in the QGIS Python environment. http://trac.osgeo.org/gdal/wiki/ConfigOptions
Setting special configure options is ...
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Trying to import Dutch Infrastructure GML using OGR GMLAS driver, but no geometries?
I have some Dutch Infrastructure GML files that I'm trying to display in GeoServer. Step 1 is to import the GML into PostGIS and while I can make it work using the OGR GML driver, I end up with a ...
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Creating simple citygml 3D models based on 2D shapefiles (alkis) shp2gml using Python?
How can I create a simple LoD1 citygml-model using Python?
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Upload KML / GML / GeoJson to Geoserver through Rest API
What is the best option, if any, to upload a vector format like GeoJson, and or GML to Geoserver?
The environment from which to upload will be a client web-application, so i cannot use curl. In the ...
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How to debug ogr2ogr ERROR 1: Did not get at least 2 values or invalid number of set of coordinates?
I'm trying to convert a government data contour GML (http://geo.data.linz.gv.at/katalog/geodata/hoehenschichten/2011/1m-Hoehenschichten.gml) to Shapefile.
It seems like it was created by FME:
<?...
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Convert gml to raster in QGIS
I have a dataset of type citygml (*.gml). It includes information about buildings and their rooftypes.
you can find a sample file here: https://www.opengeodata.nrw.de/produkte/geobasis/3d-gm/3d-...
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Read an INSPIRE GML in QGIS2.0 : gml:xlink resolving
I'm trying to read an INSPIRE GML, which contains internal and external links between the elements. I saw on the GDAL site that we can set environment variable in order to load this link in QGIS (http:...
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Can GeoTools parse GML CRS definitions?
A kind of branching of this question.
Soon I will need to handle GML Coordinate Reference Sysyem definitions in a Java servlet. Links:
GML OGC reference.
Concrete example.
I know that GeoTools ...
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Open with QGIS a GML file (INSPIRE schema) created with HALE studio
I'm trying to export in GML the transformed data of "Basic hydrography example" of hale studio and to add the file in QGIS, using the plugin GML application schema toolbox. The GML exported should be ...
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votes
0
answers
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PostGIS 2.0 st_geomfromgml using LineString fails with invalid GML representation [closed]
I am attempting to insert a geometry into a table using the st_geomfromgml function.
The GML is being sourced from a Geoserver WFS request.
The function call looks like this
st_geomfromgml('<?...
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