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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.

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. A binary equivalent, known as well-known binary (WKB) is used to transfer and store the same information on databases, such as PostGIS, Microsoft SQL Server and DB2.

The formats were originally defined by the Open Geospatial Consortium (OGC) and described in their Simple Feature Access and Coordinate Transformation Service specifications. The current standard definition is in the ISO/IEC 13249-3:2011 standard, "Information technology -- Database languages -- SQL multimedia and application packages -- Part 3: Spatial" (SQL/MM).

http://en.wikipedia.org/wiki/Well-known_text

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Loading MULTIPOLYGON in openlayer 3 with OL3-Google-Maps

I'm trying to load a multipolygon shape in a SATELLITE map using OL3-Google-Maps with openlayer 3, but no work. When I used a simple polygon it work. really I don't know what is the problem here. look the code: var glSat = new…
Jose Luis
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Extract and split lat long coordinates from WKT point data in R

I'm sure this will be a very straight forward answer. I am new to R and still finding my around it's data types. Currently importing data from MySQL however I can't quite figure out how to separate the columns bracketed inside a WKT point type. I am…
Praxis
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get google maps polygon inner cords

I'm developing a GIS and im working with wicket.js and WKT(jsts.js) to make union of polygons. I've drawn two polygons Then, when i make the union of these two polygons, the output polygon dont have the hole inside I've searched on the internet…
Joao Castanheira
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OpenLayers 3 get WKT Polygon string

I have an openlayers 3 map where I can draw Polygon. I would have returned the WKT String that rapresent the drawed polygon. How Can I do it? JSFiddle Code http://jsfiddle.net/michelejs/3zawt33b/7/ Here my map: map = new ol.Map({ target:…
michele
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How to add MultiPolygon do Android Google Maps v2 from WKT

I have geometries in a spatialite database. With the help of jts topology suite I managed to draw some simple polygons on google maps v2, transforming WKT in a coordinate array. But I can't figure out how to draw multipolygons correctly. The…
Miguel Ângelo Belém
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Exception indexing polygons with solr (jts not found?)

I'm having trouble setting up solr 4.10.2 to work with polygons. I try to adapt the example application to work with an field called geom with the type location_rpt. I added jts-1.13.jar to the file solr-4.10.2/example/webapps/solr.war in the…
dve
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How to use WKT?

I am doing a database assignment (TSQL), and have been given some "Well known Text" to work with. I have made the tables: drop table geometry_polygons; go drop table geometry_points; go drop table geometry_linestrings; go create table…
mcclma
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Python: export to DXF file the Shapely objects

How to export the results come from spatial operations such as buffer function on points using Shapely package for Python to a DXF file? BTW, googling wasn't so helpful this time.
Developer
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GIS sample data for testing performance

I need to test performance of queries based on spatial data. I decided to use sql server and geometry datatype. Now I need to have sample data (for example maps, cities etc). Do You know any resources that I can use to then load it into my…
gruber
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MySQL check if Point in Polygon (GeoJSON)

I have a table named fields with a column named geoJSON. The geoJSON column is of type JSON which stores an actual GeoJSON object. I am trying to take a list of coordinates which are POINTS (single latitude and longitude) and then select the rows…
recoilnetworks
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How to save WKT to postgres column with geometry data type using typeorm?

I have a table with a geom column which has the datatype of geometry. I need to save data into this table and the request being sent has the type wkt for this column. Currently there are some existing rows in the table with data in this…
Kaisin Li
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NetTopologySuite WKTReader ignores SRID

I implemented NetTopologySuite into EF Core (SQLServer). I'm getting coordinates from the Google APIs, transforming them into Point and Polygon and saving them into the database without trouble. I stringify Geometry.AsText() these types when sending…
Auguste VN
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R function to convert polygon (sf, wkt) into mask (matrix, array)

I have an image stored as matrix with grayscale for each pixel. On this image I use SLIC algorithm to divide it into areas. So I get a simple feature (sf) with polygons, I am able to extract in well-known-text (wkt). But what I really need is a…
Allerleirauh
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mapview and plot show different output for the same rasterLayer, why?

Below is the rasterLayer RASTER_slope in a plot (4 NAs are shown in white): Here is the metadata of RASTER_slope class : RasterLayer dimensions : 4, 4, 16 (nrow, ncol, ncell) resolution : 500, 500 (x, y) extent : 2227000, 2229000,…
Inder
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How to use OnClick and Draw WKT automatically on Openlayers + React + MySQL?

(1)Copy WKT strings in Blue => (2)Paste in Text Area => (3)Click Draw => (4)WKT Draw on Map WKT drawn on Map Objective: (1)Click on WKT strings in Blue => (2)WKT Draw on Map Current Problem: 1)Copy WKT strings 2)Paste inside textare 3)Click…
Zaki Rashid
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