2,588 reputation
721
bio website github.com/jlaura
location Flagstaff, AZ
age 31
visits member for 3 years, 4 months
seen 13 hours ago

I am a geography Ph.D. student at Arizona State University, with interests in FOSS, big data, spatial algorithm implementation in python, visualization, the application of cartographic techniques / spatial analysis to planetary data (Moon, Mars, Titan, etc.), and remote sensing.

My primary research focuses are in the geocomputation domain.


Jan
4
comment SpatialLite BulkLoad and Merge
@HeyOverThere I total agree and would offer the same comment if someone was asking about running queries. I would partition the data as well as 8.2 million rows is getting up there for PostGIS in a single table. This is especially true given all the columns.
Jan
3
asked SpatialLite BulkLoad and Merge
Jan
2
reviewed Approve suggested edit on Inaccurate result while clipping on gis data
Dec
10
awarded  Popular Question
Oct
28
comment How do I draw transparent polygons with ArcObjects?
While not an arcobjects solution this GIS.SE might be of interest as it describes trying to set individual polygon alpha values.
Oct
28
comment GDAL command lines on windows
Do these run without wrapping them in a python script? What is the output of gdalinfo <some raster> via the command line?
Oct
27
comment How can I create random concave polygons for test purposes?
@whuber Edited the question to assume a shapefile - so topology is not recorded within the dataset. Do you have a reference to any of the many approaches available with the context of either QGIS or GRASS? Clearly, I can densify my polygons(as topology is not stored) and write custom code to perform alterations in my polygons such that some number of them are concave. This would be in addition to the technique I offered in the question. My goal is to avoid writing such code and leverage some built-in functionality.
Oct
27
revised How can I create random concave polygons for test purposes?
added 17 characters in body
Oct
26
comment How can I create random concave polygons for test purposes?
@whuber A sample dataset consisting of just convex polygons does not simulate the convex / concave reality that one sees in applications such as congressional redistricting - this discount multipart polygons and islands (in the sense that the unit has not neighbor, not just in the case of a physical island). Additionally, a generated dataset provides the means for a priori knowledge of the optimal solution. Can you suggest any references to the perturbation method? It sounds as if this will simply introduce slivers at common edges (fixed endpoints with each edge defined by only two points).
Oct
26
revised How can I create random concave polygons for test purposes?
added 1077 characters in body
Oct
26
asked How can I create random concave polygons for test purposes?
Sep
14
answered How to average a set of n rasters using gdal or other GRASS module?
Sep
9
answered Where download sld styles for OpenStreetMap for GeoServer?
Sep
9
comment Is it possible to destroy a spatial index?
Updated with additional code. Added a comment wondering why intersections are indexed by negative long.
Sep
8
revised Is it possible to destroy a spatial index?
added 564 characters in body
Sep
8
comment Is it possible to destroy a spatial index?
Exactly my thought. I thought that perhaps it was because the variable was not going out of scope, but that does not appear to be the issue. As you said, calling soat_index again should force it to reinitialize.
Sep
8
comment Is it possible to destroy a spatial index?
Code / Pseudocode added. I can flesh in some more if needed, but these are the important parts.
Sep
8
revised Is it possible to destroy a spatial index?
added 1298 characters in body
Sep
8
comment Is it possible to destroy a spatial index?
Yes. In init() I loop through an input point layer to generate a polyline layer. The spatial index is off the poyline layer. Then split, update the point layer attribution, recreate the polyline layer. It is on the recreate that the spatial index is duplicated. I tried both reinstantiating QgsSpatialIndex and emptying it out with deleteFeature. No joy on either. I see that the API has a ~QgsSpatialIndex (destructor), but I don't think it is accessible via python.
Sep
8
comment Is it possible to destroy a spatial index?
This is within a plugin, on an in-memory layer, so the spatial index should only be created in memory.