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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Visualising WKT geometry string in QGIS

A very simple question: Is there a simple tool in QGIS to graphically visualise geometry formatted as text? Example geometry: "POLYGON((571178 6337246,571178 6402217,598061 6402217,598061 ...
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6answers
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Convert between ESRI Geometry and WKT

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 ...
11
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3answers
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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 ...
8
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1answer
4k views

Create a csv with geometry as WKT in QGIS (and choosing the field delimiter)

Is there a way to choose the field delimiter when exporting to CSV with geometry as wkt in QGIS? I have a shapefile with donut holes and I'd like to export it as a CSV. It's for a partner whose DB ...
7
votes
2answers
915 views

Converting KML files for use with Python library Shapely

I am trying to get a KML-file (wijken.kml) into Shapely. The KML-file is validated against the proper XML schema, so I guess the input is correct. Routes I have tried: 1) Converting to WKT or WKB ...
7
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1answer
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Help with PostGIS polygon geometry - non-closed rings

I've picked up a copy of the super-wicked book 'Python Geospatial Development' by Erik Westra (Amazon link), and I'm working through it. Currently, it's teaching me to load GSHHS coastline data from a ...
7
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1answer
239 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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4answers
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How to convert geometry to WKT using ArcPy?

I would like to be able to convert a single feature (or potentially many features) in an ArcGIS layer into Well Known Text (WKT) format during a geoprocessing operation using Python and ArcPy (no ...
6
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3answers
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Determine if a polygon intersects itself in OpenLayers

I let the users draw polygons and then I try to save them out to the SQL Server 2008 SQLGeography field, but it is giving me an error: Error 24200: The specified input does not represent a valid ...
6
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1answer
988 views

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 ...
6
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3answers
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.NET library to convert KML to WKT?

Anyone know of a free OpenSource .NET library i could use to convert KML to WKT? I know i can use openlayers and there are many JavaScript possibilities, but i need to do this on the back-end.
6
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1answer
730 views

projection/pyproj puzzle, and understanding SRS format

I have a shapefile that has a .prj file, with the following wkt contents: ...
6
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1answer
189 views

What is the definition for a geographic coordinate system with east/west bounds of 0 to 360

I need the coordinate system reference or a projection definition that uses geographic (i.e. lat/lon) coordinates but instead of east/west bounds being defined as 180 to -180, I need them to be ...
5
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1answer
397 views

How do you represent text in WKT

I need to label the simple-features/shapes in a Well-known text file. Is there some best practice on how to achieve this? Should I just keep the labels as separate entities linked to the WKT or is it ...
5
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2answers
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what is the best way to programmatically convert between WKT and Proj4 string?

some shapefiles have a .prj file associated with it. and the .prj file contains the projection info of the shapefile in the format of WKT. Sometimes I need to convert WKT to proj4 string, and ...
5
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2answers
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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 ...
5
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3answers
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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 ...
4
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3answers
228 views

Does a projection's WKT reflect the computer's locale?

This should be quick - we're trying to determine if there are problems parsing some WKT text because the system locale considers the decimal separator to be a comma instead of a period. Anyone know? ...
4
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5answers
670 views

javascript WKB to WKT function

Turns out json ain'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 ...
4
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2answers
511 views

How to generate an image from WKT?

I am looking to programatically generate an image from a WKT string (or any other common format, such as WKB or SQL Spatial geography). Are there any existing libraries that allow for this? I am ...
4
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1answer
416 views

Convert Landmask file into WKT Polygon

I have a land mask file in netCDF (also in ascii, if needed) which basically consists of a lat/long pair and a boolean (1 or 0) determining if that value is over land or not. The thing is, I'm not ...
4
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1answer
911 views

Write out a WKT file from a loaded shapefile

We are looking to load and display a shapefile, simple polygons, then write out a WKT string of that shapefile and have the user save it somewhere. Does anyone have some code snippets of that very ...
4
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2answers
167 views

can Well Known Text tables be used effectively, stored in Access or Base?

My question is: How do I import WKT text data back into QGIS, and how useful could Base or Access be in storing the data using WKT rather than spatially enabling it within a proper GIS database, like ...
4
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0answers
31 views

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 ...
4
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0answers
215 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 ...
3
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4answers
625 views

converting oracle geometry to postgis with 3d data (wkt?)

I am converting Oracle spatial database to postgis. Most of of the spatial data is 2.5d. Meaning we have a Z-coordinate which indicates the depth/height of the element compared to soil level. Getting ...
3
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2answers
2k views

Is there any efficient way to convert Geojson to WKT?

I want to use ST_GeomFromText() to load vector data to PostGIS. However, I don't know how to convert from Geojson type to WKT. N.B. I know I can use OGR2OGR to upload the geojson directly, but I just ...
3
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1answer
297 views

SQLServer generating invalid WKT

I am a GIS novice using SQL 2008, with C# and the NetTopologySuite WKTReader type to work with some geometries. I have some data which I have been able to save into the database but when I read back ...
3
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1answer
2k views

What's the proper format for WKT linestrings when importing into QGIS?

I'm trying to run the following test CSV through the Delimited Text plugin as WKT data: oid,Line 1,LINESTRING((45.554194 -122.686101, 45.433001 -122.762632)) 2,LINESTRING((45.432505 -122.598327, ...
3
votes
2answers
406 views

Google Maps Polygon to WKT

I need to convert a Google Maps polygon object (can has multi paths and holes) to wkt string (multipolygon) at client. Then i'll able to save polygon as geography in Sql Server 2012. I tried Wicket ...
3
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3answers
382 views

I have a list of coordinates that make up a route - how can I easily render this shape on a map?

Additional info - I don't need this to be on a map - I just need the shape of the route. Is there anything that can return that shape easily? The list of coordinates are in an xml document and I'd ...
3
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1answer
285 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 ...
3
votes
1answer
191 views

How can I get KML into JTS TestBuilder?

JTS Topology Suite TestBuilder supports WKT, WKB and GML inputs. What's a quick and easy way to get the geometry for a KML feature into one of these formats for input into JTS TestBuilder? For ...
3
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1answer
21 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, ...
3
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1answer
196 views

Problem with precision when convert from WKT to shapefile

I have a problem with converting from WKT to shapefile in pygdal. In wkt I have fields with precision (for example real 7.2). When I create a shapefile I have field numeric with no precision (numeric ...
3
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0answers
110 views

PostGis functions vs. EWKT [duplicate]

While using PostGis, we can query using EWKT format like: SRID=4326;POINT(lon lat) or use the functions defined by PostGis itself. For example: ST_SetSRID( ST_MakePoint( lon , lat ) , 4326 ) I'm ...
3
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0answers
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What is the best way to convert WKT String to GML String

What is the best way to programatically 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 ...
3
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0answers
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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 ...
2
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3answers
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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
2
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2answers
704 views

How to read csv with WKT geometry in Arcmap?

I have found several parcels I need on a county map viewer. However, the only option to download any of the data is found on a click context menu to "Copy selection as csv" which gives me this: ...
2
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1answer
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How to convert a shapefile to WKT?

I'm trying to convert a shapefile into the simple Well Known Text (WKT) format in the example below (from http://en.wikipedia.org/wiki/Well-known_text). MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)), ...
2
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2answers
517 views

wkb/wkt according to OGC

how can i store my coordinates in wkb.. i want to know its implementation of wkb and wkt in db .. any one can please guide me.
2
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1answer
427 views

Can you explain this WKT multipolygon format?

I am confused by the output I'm getting from ogr2ogr when converting a shapefile to WKT. What I'm expecting to see is something in the form below (from Wikipedia): MULTIPOLYGON (((40 40, 20 45, 45 ...
2
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3answers
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how to extract lat long from WKT data?

i want to extract lat long form WKT data and stores into arary list i have tried one solution which is proposed by a user but it has some problems String str = tv.getText().toString(); str = ...
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3answers
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How to create Esri Flex Geometry from WKT

I am working with Esri flex 2.3 API, I am also using Abode BlazeDS for server side binding. I am sending a geometry as WKT from server into my flex client and I am looking for a way to convert the ...
2
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1answer
424 views

Converting wkt to geojson with OpenLayers

I am trying to convert wkt to geojson wit OpenLayers. I wrote my code based on this question (geojson to wkt). That's what I have so far, but it is not working. Any ideas? var = ...
2
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1answer
36 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?
2
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1answer
377 views

Detecting invalid WKT in text column in SQL Server

I've got a whole load of WKT data in a SQL Server table, of which I'm trying to detect the validity. I'm currently doing a query like this: UPDATE f SET f."CurrentGeomValid" = ...
2
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1answer
115 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. ...
2
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1answer
254 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?