Unanswered Questions
12
votes
2answers
469 views
Group polygon features to match a set of specifications
I have two different sets of polygon features (398 census tracts and 80 ZIP codes) that each roll up to a larger feature (a US county). Though census tracts are smaller than ZIP codes, they do not ...
9
votes
2answers
1k views
Why does one part of GML -> KML conversion not work on Google Maps?
Brand new to all of this, not even sure this is the right forum to ask in...
I have a client who wants to visualise cancer incidence and mortality rates by local/unitary authority across Great ...
8
votes
0answers
154 views
Is it possible to generate a boustrophedon pattern which fill a vector Region with GRASS?
Every thing is in the title...
I have a vector region in GRASS. And I would like to generate a vector (a polyline) beeing the bostrophedon pattern which fill this region.
In the picture bellow, I ...
8
votes
0answers
145 views
Point sampling along a pole-wrapping coastline with PostGIS
I am working on a task that requires me to get sample points every 1000 km along coastlines, and have run into a problem with Antarctica. From what I can tell, it seems to be an issue with the use of ...
8
votes
1answer
4k views
Cheapest centimeter accurate satellite positioning (GNSS/GPS)
I am looking for a cheapest possible GNSS/GPS setup with a centimeter precision without much HW hacking. I am not able to produce my PCB or do any soldering (though I would do that if there is no ...
8
votes
1answer
2k views
Generating Interactive Tiles using Nodejs, Mapnik, and PostGIS for Leaflet
I am looking to do something like this but where I have all the data on the same server.
I've been following through the set of tutorials @ sparkgeo.com/labs/big/ and I'm having some difficulty. ...
8
votes
1answer
706 views
ArcGIS Server 10.1 - GPU Processing Support
Does ArcGIS Server 10.1 or any of its extensions (e.g. 3D Analyst, Spatial Analyst) take advantage of GPU processing?
Dell have a new server, the R820, that has an option to include a GPU. Hence the ...
7
votes
1answer
91 views
How to minimise number of dynamic pages to map scattered point
From time to time I have to produce mapbook to show points of interest. First step to create pages, using regular mesh:
I don't like the solution because a) there are some pages with single points ...
7
votes
0answers
105 views
Best way to cut linestrings with points
i was checking the best way to cut linestrings by points.
The scenario is: lots of streets, need the segments cut by intersect points, kind of this:
I got
linestrings (full uncuted by points) ...
7
votes
0answers
1k views
Reprojecting WGS 1984 Web Mercator (EPSG:3857) in Python with GDAL
I am reprojecting rasters in python using GDAL. I need to project several tiffs from geographic WGS 84 coordinates to WGS 1984 Web Mercator (Auxiliary Sphere), in order to use them later in Openlayers ...
7
votes
0answers
301 views
Postgis - extrude a polygon
I want to extrude a polygon shape in postgis to create a pseudo 3D effect. To this end I have written a crude function to achieve it. This is very much test code and it creates a new Y vertice for ...
7
votes
1answer
344 views
Generate ArcGIS spatial bookmarks from feature envelope
Curious if anyone has some code that would rip through a feature class and generate a spatial bookmark for each feature's envelope. There can be a field in the feature class to hold the bookmark's ...
6
votes
0answers
71 views
Python/arcGIS to create outline around points (isochrone)
I am trying to generate my own iso-chrones using Google and Python and have reached a point where I can produce two data-sets which I would like to combine in the following way:
Points (reachable ...
6
votes
2answers
178 views
Extract DEM and DTM information from LIDAR image using E-Cognition
I´m trying to extract DEM and DTM from a LIDAR file. I just rasterize the image but then I don´t know which algorithm I need to apply to obtain the DEM and DTM information in different models to be ...
6
votes
2answers
176 views
What controls the direction of TopoGeometry Linestrings?
In PostGIS, what if anything controls the direction that topogeometry LINESTRINGs will have when converted to geometry?
It doesn't appear to be the order in which the edges are listed in the call to ...
