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seen Dec 18 at 18:42

Hello!

I use PostgreSQL, PostGIS, PHP, Javascript, jQuery, HTML5, XML, XSLT, and others.


Dec
14
awarded  Popular Question
Oct
9
comment How to use ST_DelaunayTriangles to construct a Voronoi diagram?
See this answer to install ST_DelaunayTriangles in Linux Debian Stable.
Oct
9
comment How to use ST_DelaunayTriangles to construct a Voronoi diagram?
See this answer to install ST_DelaunayTriangles in Linux Debian Stable.
Oct
8
accepted How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
Oct
8
answered How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
Oct
7
comment How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
... This is for UBUBTU, perhaps I can use for Debian Stable.
Oct
7
comment How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
.. hum, your link to compatatibility chart says "(...) requires both PostGIS 2.1 and GEOS 3.4+. 3.4 also brought ST_DelaunayTriangles so you won't get that in 2.1 if you don't compile for 3.4+."... well, how to "compile for 3.4"?!
Oct
7
comment How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
The instrutins are good clue, but there are a apt-get install that only installs "libgeos-3.3.3"... Perhaps this answer
Oct
7
comment How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
@janechii, thanks (!). I edited. Perhaps must use apt-get remove purge libgeos-3.3? How check if there are two GEOS's? ... Or as suggested by JohnBarça, I need have to resort to building from source... No rationale option?
Oct
7
revised How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
added 564 characters in body
Oct
6
comment How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
Will check this today: 1 and 2 to fix.
Oct
4
asked How to update PostGIS 2.1 to use `ST_DelaunayTriangles()`
Oct
2
accepted How to use ST_DelaunayTriangles to construct a Voronoi diagram?
Oct
1
comment How to use ST_DelaunayTriangles to construct a Voronoi diagram?
Good illustrations and explanation, very didactic!   You posted all that I need (!), but this days I not have Postgis2.1 to test... Can I check here (as comment) some questions that any one can answer by testing?   1) the ST_Polygonize "creates a GeometryCollection containing possible polygons", they are all the Voronoi cells, correct?   2) about performance, you think your centroid-based solution have similar CPU-time than "all the math of perpendicular bisectors calculation"?
Sep
30
comment How to use ST_DelaunayTriangles to construct a Voronoi diagram?
Good clue, perhaps a solution (!). I need to test, but can't now... Analysing: you use ST_ConvexHull and ST_Centroid instead "perpendicular bisectors" as in the direct algorithm suggested by my ref1/Kenneth Sloa.‌​.. Why not the direct solution?
Sep
27
comment Cutting out depth information in raster. Calculating volume in Qgis
Can you use PostGIS? Is a simple MapAlgebra operation using intersection and something like pixel_volume = pixel_area*pixel_value of bathymetric image.
Sep
24
awarded  Autobiographer
Sep
24
comment How to combine raster and attribute table in QGIS?
You can do this at database, ex. if you using PostGIS.
Sep
24
comment PHP examples to replicate FeatureServer capabilities
@Gery, I agree zimmi, here an example where the webservice/ajax is a pure SQL, PHP need only to request the correct SQL function.
Sep
23
asked How to use ST_DelaunayTriangles to construct a Voronoi diagram?