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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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How does MYSQL accept the WKT representation of a polygon with holes?

I have a set of coordinates that creates a polygon with holes in it. I'm using qgis with mmqgis to extract. How does MYSQL accept the WKT representation of a polygon with holes? By holes I mean ...
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1answer
555 views

OpenLayers - changing layer type (wms to OSM) and WKT transformation problems

I've created the very simple tool which utilizes OpenLayers.Format.WKT with DrawFeature - polygon and ModifyFeature together, so I can create and modify, load and save polygons in/from WKT format. I'...
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1answer
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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" = geometry::...
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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 ...
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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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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 ...
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2answers
459 views

WKT number format inconsistent?

The WKT specification allows both period and comma to be the decimal separator in floating-point numbers (section 7.2.1): <decimal point> ::= <period> | <comma> However, a comma ...
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1answer
417 views

ArcSDE/ST_Geometry: Can I store polygon and point geometries in same row?

In the system I'm building, we've got a facility that can be represented as either a point, or a point within a polygon (the point in the polygon may or may not be the polygon's centroid). I'm using ...
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2answers
537 views

QGIS on Mac WKT import problem

QGIS 1.8.0 Mac OSX 10.6.8 These problems seem to be specific to Mac, as two Windows users don't have the problem. Import a file as a vector: TEST.CSV id;wkt 1;"POLYGON((10 10,20 20,20 30,20 10))"...
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Plotting large numbers of objects on a chart using R and WKT format

I am retrieving thousands of geometry lines in WKT format from a Microsoft SQL Server database. I would like to plot all of those lines in one map, but I am having some difficulty with the code. How ...
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1answer
4k 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 30,...
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4answers
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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 ...
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1answer
579 views

Point plus distance along great circle using RGeo or WKT

I'm racking my brains (and google) trying to figure out how to get RGeo to do the following geospatial calculation: Imagine I start off at some arbitrary geographic point (let's say (45, 45) which ...
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1answer
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Geostationary satellite projection to be introduced in GDAL

I'm working on raster files and their spatial reference system is: PROJCS["Geostationary_Satellite", GEOGCS["GCS_Unknown datum based upon the custom ellipsoid", DATUM["D_Not specified (...
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1answer
439 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 ...
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2answers
631 views

SQL Server STpointfromText comes from PHP into javascript as garbage

Sorry for the sloppy title. Here's the scenario - I have a table in SQL Server 2008 R2 It has a geographyColumn, created thusly: add geographyColumn as geography::STPointFromText('POINT('+convert(...
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1answer
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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 ...
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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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1answer
802 views

Mapnik WKT rendering problem

I have a rendering problem with the mapnik GEOS plugin. I try to input a polygon WKT definition containing floats with around 16 digits. Mapnik however does not render these. When I decrease the ...
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1answer
288 views

How can I Transfer mysql wkt directly into a postgis table?

I have wkt geometry data in mysql stored in blob format. I need to get this data into a postgis db and am looking for the quickest-easiest way to do it. I have managed to select the data "ASTEXT" but ...
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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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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 ...
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1answer
881 views

What are AGF Files, how do we put them in PostGIS?

I came across term which says AGF, after Googling I found its Autodesk Geo Files, But some other say, Atlas Geo Files, Which one of them is right. I also came to know that It is an extension to WKT ...
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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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1answer
531 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 ...
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2answers
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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 ...
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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 ...
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1answer
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projection/pyproj puzzle, and understanding SRS format

I have a shapefile that has a .prj file, with the following wkt contents: PROJCS["NAD_1927_StatePlane_New_York_West_FIPS_3103",GEOGCS["GCS_North_American_1927",DATUM["D_North_American_1927",SPHEROID["...
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1answer
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How to get elem_info array from WKT or JTS Geometry in Java?

I have Well Known Text (WKT) string with geometry. Now I want to create Oracle Mapviewer SdoGeometry, which needs sdo_elem_info array as one of arguments which is an array of doubles. How can I ...
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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.
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1answer
390 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 ...
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1answer
693 views

How to resize layer using .prj (WKT) projection? (Geographic Coordinate System)

Briefly: How to parametrize .prj WKT file so that I can perform 7 point tranformation (wiki). I know how false_easting and false_northing params work, but how can I adjust scale? I do not mean ...
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1answer
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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 ...
4
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1answer
564 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 ...
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3answers
256 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? ...
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2answers
894 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.