7,399 reputation
660150
bio website djq.me
location Cambridge, MA
age
visits member for 4 years, 9 months
seen 17 hours ago

interested in postgis, geodjango, qgis, python and R

cofounder of coUrbanize

tweet tweet: @djq


Mar
10
comment Unable to create Polygon using Geodjango admin interface
How are you saving the polygon on the map side? Also, maybe this is just a typo in the question but you have models.Polygone written down.
Jan
2
comment Trouble merging 2 rasters using qgis
Just a thought, but could you try ticking the layer stack option to see if it produces a different result? According to docs (gdal.org/gdal_merge.html ) it should "Place each input file into a separate stacked band."
Jan
2
comment Trouble merging 2 rasters using qgis
Did you try changing the color range on the merged raster? I wonder if it would illustrate what might be going wrong.
Dec
26
comment How to invoke a WFS service from command line?
hmm, on OSX so not sure how it works on a non-unix environment. The -o filename.gml just stores the output. What do you get when you type curl --help
Dec
23
comment PostGIS: Ensure Intersection of 2 Polygons results in a Polygon
Could you add in a WHERE clause where you check the resulting area is greater than 0?
Dec
21
comment How to generalize a polygon file and maintain topology in QGIS?
oops, missed the QGIS only aspect. QGIS does handle geojson though; I wonder if it would make sense to work in the topojson simplification functionality into a QGIS plugin to make it accessible to non-programmers
Dec
19
comment What is the file upload limit on CartoDB?
How big are the files uncompressed? Also, it might be a good question for CartoDB help!
Dec
19
comment Help with Python/GDAL documentation
@AlexanderKamenev I edited your question for clarity - can you check that I accurately described your goal at the end?
Dec
19
comment Errors when using the Corridor Designer tool from Arctoolbox
Can you provide some more information about what your input data is, and what the corridor Designer ArcToolbox is? Also, I added the raster tag to the question - I assume that's what you are using!
Dec
19
comment Open layer plugin in Qgis 2.6.1 crashes and errors with zoom
Do you have most recent version of OpenLayers plugin? I had a similar problem. Another way I fixed this when it was crashing, was to make sure I loaded a layer with ESPG:4326 - this seemed to help the plugin figure out the bounds of what I was looking at.
Dec
15
comment Creating map gores in ArcGIS for Desktop?
You might find this previous question useful: gis.stackexchange.com/questions/53578/…
Dec
1
comment Applying version control to ArcGIS Models
Could not agree more about the concept of reproducible research. To me it is the most compelling reason why researchers should be using OSS.
Nov
30
comment Looking for succesful implementaion of PPDM in form of geodatabase
Is PPDM an abbreviation of Professional Petroleum Data Management?
Nov
30
comment Modeling SQL Query to add statistical data to a geometry
Do you have to do it in SQL? It could be easier to do it in something like R, where you connect to the SQL DB, and have the ability to store intermediate results in dataframes throughout a script. Not saying it can't be done in SQL but long term, it might be more legible in another language.
Nov
29
comment Draw line overlays and center map
No need to apologize! We all have to start somewhere....
Nov
26
comment Best program or tool for visualising big data sets really fast 10-20 GB data if the users don't know squat about GIS?
I think this question needs to be much more specific to result in useful answers. 10-20 GB of mostly vector data is very vague. Are they points? Polygons? Do you want users to be able to choose cartographic styles? Zoom levels? See individual features? GPU considerations don't really seem relevant this early on.
Nov
26
comment Visualize large amount of geopoints with Geoserver and PostGIS
I expanded my answer to describe the general process
Nov
24
comment Simplifying geometries and calculating non-spatial averages
'zooming' suggests that you are viewing the data via a viewer of some sort; it's not an inherent property that you can calculate. If you have some spatial unit that you can aggregate upwards, perhaps you could use that? Can you post an example of the data illustrating the table structure?
Nov
20
comment Computing intersections for each geometry in a table
Out of curiosity, is a.id < b.id better than a.id != b.id as you will reduce the total number of queries?
Nov
13
comment List of useful Add-Ins for ArcGIS Desktop?
This is a four year old comment that's obsolete. While short, I don't think it needs to be expanded.