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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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 ...
11
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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 ...
10
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1answer
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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 ...
9
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3answers
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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 ...
8
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1answer
7k 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
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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 ...
7
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2answers
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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
345 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 ...
6
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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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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 ...
6
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2answers
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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 ...
6
votes
3answers
2k views

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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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
915 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
219 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
454 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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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 ...
5
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0answers
73 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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3answers
230 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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4answers
142 views

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 ...
4
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2answers
2k 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 ...
4
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1answer
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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, ...
4
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2answers
598 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
464 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
1k 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
223 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
331 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
votes
4answers
989 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
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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: ...
3
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1answer
377 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
votes
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 ...
3
votes
2answers
581 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
570 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
votes
1answer
2k 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. ...
3
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1answer
884 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?
3
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1answer
240 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
67 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 ...
3
votes
2answers
306 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 ...
3
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1answer
177 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
votes
3answers
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 ...
3
votes
1answer
212 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
187 views

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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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
2
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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 ...
2
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3answers
2k views

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 = ...
2
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2answers
561 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.