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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Where can I find the WKT standard or reference?

I had a little confusion about the representation of a geometry as well-known-text (WKT). I was searching for the WKT Specs to search for the exact representation, but I did not find the Standard. Is ...
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152 views

Using WKT.writeGeometry for 'Circle' Geometry in OpenLayers?

In my application which I'm building using OpenLayers3, I'm trying to extract the geometry of a feature to WKT using var format = new ol.format.WKT(); console.log(format.writeGeometry(geometry)); by ...
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41 views

Adding a column of WKT format in the table (postgreSQL)

I want to include this column of data that are in WKT format (they are mostly straight lines). What data type should I use? I need to create this database for mapping. There are about 30000 features ...
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269 views

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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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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56 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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34 views

Understanding the format: WKB from WKT and how to convert the first into the latter

I don't understand which kind of format I have my data. The column name is wkb_geom, so I supposed that data were in WKB format, but then I was checking around and I couldn't find example of it. Data ...
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4answers
168 views

Fix Self Intersecting Polygons Manually

I are looking to implement a method to fix self-intersecting polygons by editing the vertex order. We want to take the polygon rings and re-arrange/add in vertices to make a valid polygon. This is ...
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32 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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40 views

Problem with importing WKT to PostGIS

I'm trying to import WKT (http://polygons.openstreetmap.fr/get_wkt.py?id=2413177&params=0 - boundary of one of districts of Łódź) into PostGIS database and convert it to geometry. I've created ...
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52 views

How can I get public transport maps in WKT format?

I can get street maps from openstreetmaps.org (XML) and convert it into WKT with the tool osm2wkt. There are several people creating specialist public transport maps: The Transport Map layer on ...
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66 views

Parsing XML file with hundred polygons using OpenLayers

I'm using this script but It's not working. <script type="text/javascript"> var raster = new ol.layer.Tile({ source: new ol.source.OSM() }); var xml = new OpenLayers.Format.XML(), wkt = new ...
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33 views

PyQGIS - Syntax for importing WKT file

I couldn't find any proper example of how to import a .csv with WKT coordinates (Polygon) in PyQGIS. Here are more details on my .csv. I am working with polygons. The delimiter is a semi colum, and ...
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1answer
29 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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48 views

How to add new SRS/Projection/WKT to the GDAL database

I'm using GeoServer, OpenLayers(3.0) and the GDAL utilities. GeoServer has one (or more) SRS/Projections that is/are NOT present in the GDAL database of SRS/Projections. I can get the well-known ...
3
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1answer
68 views

Why does projection WKT differ between osr.SpatialReference and gdalinfo

I am writing a simple geotiff using the GDAL python bindings, but the projection WKT reported by gdalinfo differs from the source. The script from osgeo import gdal, osr import numpy # Create ...
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6answers
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WKB to WKT JavaScript function

Turns out json isn't so good at transporting binary data. But with HTML5, XHR2 is now capable of transferring blobs cleanly. I'm looking to transfer binary geometry (to save bandwidth) and decode it ...
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1answer
77 views

Parsing large GeoJson geometry to WKT

I'm reading a very large json file as an InputStream in Android with JsonReader. This json has a geometry object like so.. "geometry":{ "type":"MultiPolygon", "coordinates":[ ...
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1answer
38 views

How can I convert bytes to geometry?

Recently I have reviewed that postgreSQL provides support for Geometry objects in database. But in my old sql servers I have bytes data type for shape in database. Now I want to convert those bytes ...
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42 views

GeoServer GeoJson with coodinates in WKB?

I'm using a GeoJson query to GeoServer to update data in existing sqlite database used in an android app. The geometry column in that database is in WKB format, because like this the database is ...
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4answers
6k views

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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2answers
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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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159 views

Using Terraformer to convert to WKT

I'm using Terraformer to parse some ArcGIS JSON into a Terraformer primitive. I'd like to store the geometry in PostGIS for other purposes. So I'm trying to use the WKT.convert tool to convert this ...
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36 views

NDVI Web services over Victoria australia

Does anyone know of any web services that are available where you can pass...say a WKT polygon or point and return the mean NDVI or NDVI from that point from an array of the most recent NDVI runs?
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434 views

Does OpenLayers3 support WKT format?

How can i show spatial data(Point, LineString,Polygon) on bing map using openlayer3?
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54 views

OSGEO/GDAL and Rotated Pole Grids

I have a netCDF containing a raster in a rotated pole grid. I have a script for converting the desired information to GeoTiff, however it requires projection information in the form of WKT string. ...
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36 views

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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2answers
187 views

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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60 views

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 ...
3
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1answer
179 views

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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227 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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1answer
316 views

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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61 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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49 views

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
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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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2answers
310 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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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
146 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 ...
0
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1answer
188 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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2answers
579 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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4answers
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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
379 views

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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0answers
87 views

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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2answers
569 views

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
126 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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1answer
21 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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125 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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1answer
298 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 ...