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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Max length for WKT name

First of all, sorry if this is obvious or stupid questions. I am not very familiar with geographic information system. My question is, is there max length limitation on WKT name? see the bold text ...
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How are ESRI WKT projections different from OGC WKT projections?

Does anyone know the precise list of differences between esri wkt and ogc wkt projection format strings? I know there are various tools to help convert from esri wkt to ogc wkt, incl gdal utilities ...
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Are there any online WKT editors?

I've been using QGIS and it's great. However, we can't use that because it has to be installed (please, don't ask). Instead, what we need to do are very simple administrative boundary drawings over a ...
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from shape files to a database [closed]

I've previously converted simple shape files to WKT so that I can store them in RDMS that has spatial capabilities. I'm a new user to QGIS, which I'm using to browse a shape file. But now I have a ...
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extract vertices from dbgeometry value

Who knows the elegant way to extract coordinates of polygon vertices from well known text representation of DbGeometry value? Here's my polygon for example: {POLYGON ((52.808019 -1.345367, ...
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How to change 0,360 WKT string to -180,180?

I'm reading POLYGON WKT strings using OpenLayers.Format.WKT().read(). The polygons use 0,360 longitudes but my map is -180,180. When I display the polygons on the map they are displayed outside of the ...
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147 views

WKT for local mine grid

I have been trying to create a WKT entry to use in gdalwarp etc. I need an affine transform from coordinates in MGA94 Zone 54 to our local mine grid. All efforts have so far failed, including using ...
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1k views

OpenLayers create marker (feature with icon) from WKT

I have a point object WKT. Like this: POINT (25.04568 48.221548). Also I have an icon in my project folder. My goal is to show on a map an icon that represents a feature. Can it be just a normal ...
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Shape looks like big Square in SQL Server 2008

I was provided with a polygon defined in WKT which has 4741 points and am able to insert it as a geography data type within a database in SQL Server 2008. However, when I view it using the spatial ...
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Converting between Esri Geometry and WKT using ArcObjects?

It seems like there is no means of converting an ArcObjects geometry to the Well-Known Text representation (and vice versa) in ArcGIS ArcObjects API. The only thing I was able to find is conversion to ...
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53 views

strange result of spatial functions postgis

I have a problem with different result of spatial functions for same geometry. For some reason result I get when I use geometry from database is different then result when I load same geometry from ...
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How to change Axis Order when transfering data from WFS to Postgis DB

I am using GeoKettle to transfer data from a WFS service to a Postgis DB. The projection of the geometries is WGS 84 : GEOGCS["WGS 84", DATUM["World Geodetic System 1984", SPHEROID["WGS 84", ...
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1answer
643 views

Parameter values to create a vector grid with 1km x 1km cells?

I created a shapefile from WKT in QGIS using the values from this link. I want to create a vector grid with 1kmx1km cells but I can't figure out what values need to be set for the X and Y parameters. ...
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103 views

What is the best way to get from wkt to shapefile in Python?

I am querying tables from a SQL-Server database and would like to convert the table into a shapefile. It has wkt geometries and wkb as columns in the table, along with other attributes that need to ...
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224 views

Does OpenLayers3 support WKT format?

How can i show spatial data(Point, LineString,Polygon) on bing map using openlayer3?
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4answers
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How do you generate WKT from a graphic drawn on a map?

All, In order to do some quick analysis using SQL spatial, I'd like to generate spatial objects using the STGeomFromText / ST_GeomFromText function. With point data, I can do this by geocoding an ...
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1answer
78 views

Ideal file format for QGIS that allows mixed geometry types?

I have a spreadsheet for an archaeological project that is hosted on Google docs. This allows multiple contributors to edit and update the table as revisions and field data comes in. The table is not ...
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1answer
95 views

How to transfer a WKT string from OpenLayers to Geoserver or PostGIS?

Supposing I have created a Vector Layer in OpenLayers and then transformed it to WKT or GeoJson, how can I export it from OpenLayers, and possible import it to PostGIS or GeoServer?
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538 views

Project WGS84 to Google using MapGuide and WKT

I'm having trouble projecting a simple WGS84 formatted layer over google maps. I can't find a good WKT "API" that not only shows parameters, but explains what each parameter is. The coordinate system ...
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488 views

Online WKT and GeoJSON viewer

I once found a great but simple webpage that has a drop down with several text-based GIS formats such as GeoJSON and WKT, and a text box to copy/paste your data. The feature is then drawn on a world ...
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Looking for a pythonic way to calculate the length of a WKT linestring

I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
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3answers
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Openlayer is very slow when using WKT Multipolygon with a large number of Points

I'm showing the boundaries of cyprus regions using openlayers with vector layer, I get the coords from a shapefile which has a lot of points, for instance some regions can have a multipolygon with in ...
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R PostGIS convert SpatialPolygon to PostGIS table

I've been having some success in scraping some webdata and converting it from HTML to spatial data as originally asked here: Parse PHP/HTML to shapefile or similar I've been using R to both fetch the ...
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Iterating polygons on a SpatialPolygonsDataFrame in R with readWKT

I have fetched some data (39 objects) from my PostGIS database and converted this data into a matrix: rs <- dbSendQuery(con, "SELECT ST_AsText(polygon_accumulation) AS ShapeWKT from ...
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1answer
87 views

Java library for reading geojson from MySQL

I am looking for a way to retrieve mysql geometry data as geojson from the database either using a java library or for converting wkt to geojson using either java or javascript. Currently I am doing ...
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16 views

Is OpenLayers compatible with OGC WKT SRS definitions?

I'm trying to use WKT in OpenLayers. Proj4js seems to have no problem with this but the OGC definition describes the units as "US survey foot" whereas OpenLayers has an INCHES_PER_UNIT definition of ...
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86 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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150 views

Convert WKT (or geojson) geometry to numpy array of coordinates

I am looking for the fastest way to convert WKT or geojson geometry from string to numpy array of coordinates. Is it possible to do it strictly in Python and without creating geometry object such ...
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1answer
49 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, ...
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360 views

Returning string from OpenLayers.Format.WKT write? [closed]

How to return a string from OpenLayers.Format.WKT write this.innerHTML = new OpenLayers.Format.WKT().write( layer.selectedFeatures[0] ); my full code is like this please suggest me... ...
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15 views

Failing to get wkt to reference for a multiline

I apologize, I'm quite new to WKT (and most everything else). I have a shape that I've exported to csv. & geoJson to be loaded into CartoDB. Unfortunately, the geoJson doesn't work so I am trying ...
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216 views

How can I convert WKT to SHP?

Using ArcGIS, ArcInfo and fme, I would like to transform data which contains wkt geometries (points, lines and polygons) into SHP. Has anyone a workflow for doing such a transformation?
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Is there a limit to the number of polygon points you can export to CSV in QGIS 2.4?

Using QGIS 2.4 I am currently importing a csv file with ~30,000 polygons (polygons in WKT format). I also have a United States shapefile. I have used the Clip function to get only the polygons that ...
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149 views

How to create WKT file readable by QGIS 2.4.0

I am trying to create a well-known text (wkt) file that can be imported into QGIS ver. 2.4.0 Here's a minimal working example of the geometry I wish to represent. POLYGON((-125 52, -125 21, -98 21, ...
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Converting WKB to WKT

how can i convert wkb to wkt form ... i stored coordinates in wkb but now can it will display to use in wkt form
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How to unproject WKT to WKT in .NET?

I have WKT in this format: GEOMETRYCOLLECTION(POLYGON((491990.250718 6212873.59755,491492.160493 6212904.94117,491265.64715 6212790.54445,491319.517251 6212550.36334,491579.624164 ...
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105 views

Transform wkb to gml geometry using FME

Maybe (and probably) this is stupid question, but I am totaly new to FME and geometry conversion. I need to transform WKB field from SQLServer to GML geometry using FME software. How can I do this?
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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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180 views

Reproject WKT Polygon with Javascript

I have a polygon in WKT in EPSG:4326: polygonWKT = 'POLYGON((13.215179443359373 52.588032137196755,13.42803955078125 52.592620721000365,13.454132080078125 52.46897854656702,13.347015380859375 ...
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geography, geometry, distance, and wkt - PostGIS

I'm trying to understand the data conversions that happen in PostGIS when calculating distances in SRID 4326. Why is it that when I run on my marin_jobs points table: select cast (the_geom as ...
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1answer
262 views

What are the differences between the OGC and ISO WKT/WKB specification?

Are the OGC-Simple feature access and the ISO (ISO/IEC 13249-3:2011 "Information technology - Database languages - SQL multimedia and application packages - Part 3: Spatial") significantly different ...
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1answer
116 views

Shapely WKT precision/rounding

I'm using Shapely's wkt.dumps function to get WKT from geometry objects. I can't seem to find a way to limit the precision of the coordinates. Any help is appreciated.
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66 views

Using Well-Known Text and geocoding on Load

So, I have tested adding columns with the WKT format into Carto, and it has always worked great (I tried 1 row, then 1000 random rows from our data). I geocoded it on load by naming the column with ...
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1answer
69 views

How to convert this geometry location format to a qgis usable format?

I am a beginner with regard to dealing with gis information, so please bear with me. I would be obliged if someone could help. I have data on asssembly constituencies of Delhi, with these ...
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519 views

Well-known text (wkt) validator

Is there anything like http://jsonlint.com or http://geojsonlint.com for WKT? How can I validate a complex WKT string, say e.g. a Multipolygon?
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Getting EPSG:4326 WKT data for use in Drupal Geofield [duplicate]

As I understand it, EPSG:3857 is measured in "meters" and EPSG:4326 uses latitude and longitude. In Drupal, geofield seems to want to store "EPSG:4326" data using the WKT widget -- even though the ...
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Represent full globe in Oracle Spatial

In SQL Server 2012 I can do this: -- Construct a new FullGlobe object (a WGS84 ellipsoid) DECLARE @Earth geography = 'FULLGLOBE' -- Calculate the area of the earth SELECT PlanetArea = ...
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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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QGIS 2.2 saving layer as CSV with GEOMETRY=AS_WKT not working

Just upgraded to QGIS 2.2 and it looks like saving a layer as CSV doesn't support GEOMETRY=AS_WKT anymore. The new Layer Options portion of the save dialog is cool but it looks like GEOMETRY and ...
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How to create path based on waypoints?

I am trying to map flight paths and compare historic paths with current ones (so I later need to perform some calculations as distances between them). For this task I am using QGIS on OSX 10.9.1 As ...