Questions tagged [wkt]

Well-known text (WKT) is a text markup language for representing vector geometry objects on a map, spatial reference systems of spatial objects and transformations between spatial reference systems.

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When does WKT orientation matter for polygon and multipolygon in geography spatial (left/right hand rule, counter-clockwise, clockwise)

I've decide to use sql server on Azure for my gis database. I'll be dealing with spatial Geography not Geometry. While inserting some country boundaries using the spatial data in SQL Server, some ...
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241 views

Differences beetween proj4 string and WKT

What are the differences between proj4 strings and well-known text in terms of the ability to represent a projection, other than for WKT being more human readable?
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ArcGIS and SqlServer.Types: Does feature.Shape.SpatialReference.FactoryCode == srid?

I created a test implementation of the ESRI Geometry to WKT recipe provided by @SagebrushGIS. It seems to work great, but I'm wondering if the SRID value expected by Microsoft.SqlServer.Types (...
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1k views

How to get WKT from SHAPE column in the ArcSDE geodatabase?

I have an ArcSDE geodatabase running on top of SQL Server 2008. A table for a feature layer was added from ArcCatalog. The SHAPE column is a type of int which was automatically converted from ...
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294 views

Implicitly convert Geometry to WKT string in PostGIS

Suppose I have a table defined as follows: CREATE TABLE gtest (name varchar, geom geometry); To insert, I am able to simply do this: INSERT INTO gtest VALUES ( 'Polygon', 'SRID=4326;POLYGON(...
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260 views

Storing Shapely polygons in MySQL

I have to store some polygons in a MySQL database. The polygons are in Plate Carrée (ESPG 32662) projection, but I also tried to first converting them to the usual latitude-longitude projection (ESPG ...
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218 views

Seeking example .PRJ file using WKT syntax for Concat_MT?

I've been digging into the WKT format definition found here:WKT Format with the aim of defining a PRJ with two chained affine transforms to go from a known projected system to a local grid. I've been ...
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43 views

3D wkt geometries - Parse in .Net suggests alternate form

I am having some issues with a built in .net framework class (System.Data.Spatial.DbGeometry in assembly System.Data.Entity). It turns out that this class cannot parse 3D geometries when they are ...
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155 views

GDAL c# API returned different WKT from gdalinfo

I've found completely different results in WKT strings while using gdalinfo utility and method from c# API GetProjectionRef(). In the first case the result was: PROJCS["WGS 84 / Pseudo-Mercator", ...
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291 views

Change Axis Order when transferring data from WFS to PostGIS DB

I am using GeoKettle to transfer data from a WFS service to a PostGIS database. The projection of the geometries is EPSG:4326 : GEOGCS["WGS 84", DATUM["World Geodetic System 1984", SPHEROID[...
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47 views

EPSG codes and water level datums

I'm curious if, and how, people use EPSG defined water level vertical datums such as Mean Low Water. There is specific guidance to not use the OGP EPSG definition: Remarks: Users are advised to ...
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211 views

Working with WKT data in XML File in SQL Server

Anyone have experience with importing XML files into SQL server 2008 or 2012 that have a WKT element that includes the geometry for each feature? I can get this to easily work using FME software but ...
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1answer
174 views

Max length for WKT name

Is there max length limitation on WKT name? see the bold text below: GEOGCS["GCS_Wake_Eniwetok_1960", DATUM["Wake_Eniwetok_1960", SPHEROID["Hough_1960",6378270,297]], PRIMEM["...
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64 views

What could be a proper and simple invalid WKT/WKB geometry?

We are converting a geometry table to another one and we would like to convert every invalid geometry to a single one easily identifiable by users in WKB or WKT form and not breaking the processing or ...
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2answers
88 views

Need to zoom into a vector Layer of a multipolygon

I am getting a multipolygon coordinates from DB in WKT format. I am able show the same on the map. But the problem I am facing is while zooming to center of the Multipolygon. Is there any way to zoom ...
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41 views

Getting information on geo file projection in Python?

I have many geo files with different extensions, from different sources (mid/mif, shape, geojson, dat). I'd like to get information on their projection (i've no access to epsg code). Maybe, I search ...
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201 views

Passing a WKT Polygon with interior rings to a QgsRubberBand's Geometry with PyQGIS

Starting point is that I select a geometry with the following query in QGIS DB Manager: SELECT 1 AS myid, st_buffer(st_union(wkb_geometry), 5) FROM ax_strassenverkehr WHERE unverschluesselt ILIKE '%...
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540 views

How to convert ESRI .prj WKT string to Proj4 string WITHOUT GDAL

ESRI shapefiles include a .prj file containing CRS information in Well-Known Text (WKT) format. I'm developing a software in which I need to systematically read shapefiles' CRS information, convert it ...
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135 views

How to define a Topocentric CRS in OGC WKT form?

I'm trying to construct a DerivedCRS in OGC WKT form that describes a 3D local rectangular coordinate system that is sometimes referred to as an LSR or ENU or Topocentric. It has an origin described ...
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180 views

How to convert Common Alerting Protocol (CAP) <area> to WKT

I've come across some data being sent in the CAP (http://docs.oasis-open.org/emergency/cap/v1.2/CAP-v1.2.html) format, which in turn contains an <area> element with either a polygon or circle ...
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404 views

Rails - inserting GeoJSONs into PostGIS-adapted database

I'm using Rails' PostGIS adapter and RGeo-GeoJSON gems to store/serve some simple geometries in the Postgres database, but I'm having a little trouble with my database seed file... I'd like to be able ...
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382 views

Getting H2GIS functions to work in Spherical Space?

I've been playing around with H2GIS (http://www.h2gis.org/) for a project at work and am struggling to get the H2 functions to operate in spherical space (lat/ lon), rather than cartesian space. The ...
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227 views

Proj4 WKT - Cartesian with origin to EPSG900913

I'm converting wgs84 to cartesian with origin using simple function in c# public static double[] LL_TO_XY(double latitude, double longitude, double originLatitude, double originLongitude) { ...
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226 views

QGIS Copy Attribute Table To Excel - where does the new lines come from?

I have an attribute table with 3100 lines. I selected the whole table and pressed the button 'copy selected rows to clipboard', afterwards I pasted them into an excel-table. Now I have 27 lines ...
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309 views

ogr2ogr latitute longitude conversion formats

trying to convert shape files into mysql tables. Able to create table and load data successfully using OGR2OGR. Only challenge I see is latitude/longitude is not exactly the same format as one of my ...
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469 views

Convert series of WKT to Shapefile

I have seen am ability in SQL Server 2008 Spatial Tools here that saves result of query as shapefile..I am intrested in how to do this task using C#..Is there any way to do this?I found ways to ...
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0answers
430 views

Write WKT/WKB to File Geodatabase using FGDB API

Is there a way to set the geometry of a row using either WKT or WKB with the File Geodatabase API? Is there any other way to write spatial data to the file gdb using the fgdb api without having to go ...
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206 views

Trying to convert to EPSG:27700 (Ordnance Survey) projection, unable to do so

I'm trying to code an interface that allows a user to draw a vector shape on openstreetmap, which is then converted to a WKT string, processed by the server and sent of as a WFS query to emapsite (...
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12 views

Converting feature from draw interaction to WKT string

I've problems with converting the feature which I'm getting in draw interaction into the WKT string. I saw multiple examples which looks like it should be simple but I'm always getting the following ...
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152 views

Getting well known text from varchar in redshift.

As you know, redshift does not support geometry types. There is a column in a dataset on my redshift db that has varchar column and the format looks like: ...
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1answer
379 views

including SRID in WKBWriter in Shapely doesn't work

I want to encode coordinates of LineString in WKB with the SRID included wkbwriter = shapely.geos.WKBWriter(shapely.geos.lgeos, big_endian=False, include_srid=True) geo = wkbwriter.write_hex(...
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1answer
217 views

GeoTools and GDAL: CRS WKT

I would like to achieve the same output as for GDAL using the GeoTools library: CoordinateReferenceSystem crs = CRS.decode("EPSG:32632"); String wkt = crs.toWKT(); System.out.println(wkt);...