5
votes
0answers
99 views

How to speed up simultaneous working with PostGIS layers in QGIS?

we are working on one big layer at the same time (10-20 people). Some of us use QGIS 2.8.1 and the other 2.6. The user with 2.8 have a lot of crashes (QGIS). The 2.6 users don't have this crashes but ...
5
votes
0answers
198 views

Any Examples of D3.brush() used with Leaflet?

I have a leaflet map that I have placed an SVG "on top of" using the leaflet overlay pane. I want to add a D3 brush to the overlay pane that will then update a separate chart. I've looked around for ...
5
votes
0answers
463 views

RGB satellite image in Python with Basemap

Can anyone recommend a workflow or python library that will let me work with RGB images and BaseMap (or something equivalent - could be CartoPy). I have Landsat 8 images, and can load one in python ...
5
votes
0answers
128 views

Cumulative length of polylines

I have a polyline shapefile with streams. I would like to turn this to a raster where there would be a cumulative length sum value in each pixel moving downstream. In other words, this would be an ...
5
votes
0answers
325 views

What is the function of the ESRI.ArcGIS.AddIns.targets file?

I am currently upgrading from 10.2 to 10.3 and as expected there are always some issues with recompiling addins and upgrading the the visual studio version. There is now a known issue for which ...
5
votes
0answers
108 views

Create buffer based on polyline without line end caps and without dissolving the created polygons in QGis

I have a projected line layer (Shapefile) in QGIS. For every line segment I want to create a polygon without line end caps. The resulting polygone should not be dissolved to a single one. I tried ...
5
votes
0answers
259 views

Why is QGIS georeferencer much faster on Windows than Mac?

I just went from temporarily using a Windows 7 machine with 4GB of RAM and no video card as far as I know. I'm now using a mac with 16GB of ram, etc. Its a much more powerful machine. However, QGis's ...
5
votes
0answers
631 views

PostGIS: Merge any and all adjacent polygons

I would like to do adjacency tests on a parcel (polygons) layer and merge them if they fit certain criteria (could be size). Per the picture below, I would like to merge polygons 1,2,3 and 4, but not ...
5
votes
0answers
149 views

Search Radius for Line Density

I have been working with GIS for many years but I am fairly new to the spatial analyst side of things. I am working with many satellite tracks for many different individual animals and would like to ...
5
votes
0answers
169 views

Configuration problem anaconda python in ArcGIS

I used Eclipse with PyDev to create a script in Python (windows 7 x64). My code runs perfect when I start the run in Eclipse, but when I add it as a Tool in ArcGIS 10.1, I have the following problems: ...
5
votes
0answers
121 views

How do I open MOD17A3 in ENVI such that it is properly georeferenced?

I am using ENVI 5.1 on Windows 8. I am trying to open a MOD17A3 (MODIS Net Primary Productivity standard product - L4) .hdf file which I downloaded from the USGS website. I am still a beginner at ...
5
votes
0answers
80 views

Is it possible to add an ArcGIS attachment to a row in Oracle using oracle stored procedures?

So far I have been able to attach files to features within a featureclass using the python tools and ArcObjects. Within Oracle I have been able to add features with geometries using the ST_Geometry ...
5
votes
0answers
1k views

How to render Mapbox Vector Tiles from OSM data?

I'd like to render my own vector tiles in the Mapbox Vector Tile format (MVT) format using OpenStreetMap data (ultimately for use with Mapbox's hot Mapbox GL JS client renderer). Is TileStache + ...
5
votes
0answers
68 views

QGIS Cross Section Profile Distance using Ellipsoid?

I am working with QGIS 1.8 and 2.6 and can't get any of the Cross Section Profile tools to provide the ellipsoid ("proper") distances. All the distances use geographic coordinates which are too ...
5
votes
0answers
196 views

Zonal Histogram Output Problems - No values associated with the habitat type

I have a outline of some islands (shapefile or raster) and GAP landcover data (raster). I am trying to use Zonal Histogram to create a file with a histogram of the habitat types in each island. Each ...
5
votes
0answers
94 views

Diminishing performance of gdal_polygonize in a python subprocess for GRASS to PostgreSQL

I have written a python script to polygonize GRASS rasters into a PostgreSQL database using the gdal utility gdal_polygonize: sub.call('gdal_polygonize.py -8 gdb/quercus/{0}/cellhd/{1} -f ...
5
votes
0answers
77 views

Generate a series of ellipses on a line

I am trying to create a series of ellipses (mocked up in green below) of defined dimensions along a line. I have got as far as generating regularly spaced points along the line that are attributed ...
5
votes
0answers
219 views

Grouping carpool participant addresses for network

I have a list of addresses of people participating in carpools to a workplace and a list of cars given by the workplace. Both lists change daily. I need to group people by their addresses and assign ...
5
votes
0answers
503 views

QGIS 2.4.0-Chugiak: How to threshold NDVI to calculate emissivity for land surface temperature

I am analysing urban heat island using thermal band 6 of landsat TM-5 sensor with respect to Normalized difference vegetation index that derived from the Band 3(Red) and Band 4(NIR). Lansat TM years ...
5
votes
0answers
93 views

What Does the Cell Value in a Composite Raster Mean?

When I make a composite raster in QGIS using the GRASS r.composite tool and then click on a certain cell I get these values in the blue/green/red/composite rasters: blue = 124 green = 124 red = 172 ...
5
votes
0answers
51 views

Access multiple rasters with GeoServer

I am curious if anyone knows if, and how, it would be possible to configure GeoServer to provide download (GetCoverage) capabilities to multiple adjacent rasters. A GeoServer mosaic comes close, but ...
5
votes
0answers
96 views

Adding data from PostgreSQL to Query Layer of ArcGIS for Desktop warns that given coordinate references are incompatible?

When adding data from PostgreSQL in a Query Layer I get the warning "The given coordinate references are incompatible" I have added many other layers with the same properties no problems, but I have ...
5
votes
0answers
110 views

Interpolating species data from sample points in a small area

I have sample data from a small site (10 acres) which shows the number of occurrences of a particular species of snail over two sampling periods (fall and spring sampling). I want to try and ...
5
votes
0answers
71 views

Null Values in Geographically Weighted Regression Analysis

Some of my explanatory variables have a few null values for certain polygons. Can GWR handle these, or should I remove the whole polygon and all data (dep, ind variables for that particular polygon)? ...
5
votes
0answers
150 views

Is there a limitation on the numbers of layers that can be displayed in QGIS?

I have been looking for an answer to this question for the last several weeks, so hope that someone here has encountered the same issue and has a viable solution to my problem. I am currently using ...
5
votes
0answers
272 views

Performing buffering and intersection with script in PyQGIS

I wrote a script that performs the intersection of two layers: The first Layer -> layer1, represents the rivers The second Layer -> layer2, represents a set of circular dots distributed in a ...
5
votes
0answers
140 views

Rotating annotation by angle using center point of annotations (with baseline alignment) in ArcMap

Is it possible to rotate annotation (in ESRI Annotation FeatureClass) by angle so that new position would be calculated based on annotation center point (not alignment, as it is set to baseline, ...
5
votes
0answers
145 views

GeoServer ImageMosaic PostGIS index update

I use GeoServer where I created an ImageMosaic storage following this manual. When I create new datastore, all *.tif files are indexed into DB (PostgreSQL with PostGIS). How can I create new index in ...
5
votes
0answers
158 views

how are range domains validated when editing a feature service in ArcGIS Online?

I have a feature class and a range domain is applied to a field. I know we can use the "Validate Features" command for validation. My question is that when the feature class is published to ArcGIS ...
5
votes
0answers
236 views

How do I parse the file format for attributes in Raster Product Format (RPF) maps and imagery?

I'm trying to implement an open-source NITF reader (using only java, no external libraries such as GDAL or NITRO), and its mostly going OK. However I'm having trouble understanding the RPF extensions, ...
5
votes
0answers
131 views

Is there a limit to the number of polygon points you can export to CSV in QGIS 2.4?

Using QGIS 2.4 I am currently importing a csv file with ~30,000 polygons (polygons in WKT format). I also have a United States shapefile. I have used the Clip function to get only the polygons that ...
5
votes
0answers
279 views

Has anyone used ArcGIS for 'automatically' detecting lineaments from a high-resolution (1m) DEM?

I have a set of DEM's produced from LIDAR data. I am wondering if anyone is familiar with or knew of any published research papers which looked at (semi-)automatically detecting lineaments /or ...
5
votes
0answers
127 views

Servers that implement OGC Geo/Time OpenSearch

The OGC is close to publishing the "OpenSearch Geo and Time Extensions", which can be downloaded from http://www.opengeospatial.org/standards/requests/116. That specification is based on, but extends, ...
5
votes
0answers
192 views

How do I simplify the straight sections of (multi)Linestring in PostGres/PostGis leaving the curved sections untouched

I have (multi)linestrings containing upwards of 5000 points and I want to perform two simplifications possibly using Ramer Douglas Peucker or alternative methods in PostGis The (multi)linestrings ...
5
votes
0answers
279 views

QGIS: How to reverse vertex ordering in polygons

I am working with an Oracle spatial connection in QGIS through which I am accessing and editing a vector layer. I find that when I edit a geometry, the vertex ordering is reversed (to clockwise in the ...
5
votes
0answers
154 views

Distribute QGis plugin which depends on certain Python packages

I developed a plugin for Qgis which depends on some Python packages. On Linux and Mac, this is not really a problem because I can easily install them with the system pip command. Windows is another ...
5
votes
0answers
140 views

Why are date vaules displaying a trailing 'Z' when layers are published with Geoserver and a PostGIS data store?

I have published various layers using Geoserver 2.2.x with a PostGIS 2.0.1 (PostgreSQL 9.1.x) data store. Fields that only have date values and not time/timestamp related values are stored as date. ...
5
votes
0answers
452 views

How to convert a raster (array) to a NetworkX graph and do a * search?

I want to use a slope-raster for a a_star path analysis in NetworkX. I am using Python for this project. My test raster looks like this First I read in the raster with GDAL input_raster = ...
5
votes
0answers
439 views

Weather conditions forecasting / interpolation

I'm trying to carry out weather conditions interpolations. I have information of 92 weather stations for 800,000 km2. As you can imagine the extension of land is huge and I need some kind or weather ...
5
votes
0answers
463 views

How do I install Orfeo toolbox and Qgis 1.9?

I'm having a lot of trouble getting Orfeo toolbox and Qgis 2.0 working. I followed the qgis wiki instructios, added the ppa, installed qgis 1.9 (it's beautiful, great work!). But when i tried to ...
5
votes
0answers
505 views

Finding poi using st_dwithin in postgis

I am not familiar with gis or writing sql, so my understanding in this field is lacking. I have a hundreds of lat/lng geographic coordinates stored in a single table called Places like this: ID | ...
5
votes
0answers
254 views

QGIS does not read ESRI Geodatabase correctly

I have a geodatabase from the EPA that does not seem to me reading correctly with Quantum GIS. QGIS Version 1.8.0 (Lisboa) and GDAL/OGR 1.9.2 When I open the attribute table the first two columns ...
5
votes
0answers
180 views

Is GeoExt styler extension available for Geoserver 2.3.3?

I've switched from my older version of geoserver to geoserver 2.3.3. In the older version, the styler worked just fine, but I could'nt find a styler extension that matched the new version. I tried ...
5
votes
0answers
735 views

Using stat_density2d with coord_map in ggplot2

In my example I am plotting a shapefile for all England & Wales, however I'm interested in the greater London area. If I allow ggplot to simply default and display the entire shapefile then the ...
5
votes
0answers
487 views

Find points that fall within a radius using Hibernate Spatial

I am using hibernate spatial and postgis and i want to find the points that fall within a certain radius. Using this SQL: SELECT name FROM institution WHERE ...
5
votes
0answers
1k views

How do I solve Gdalwarp error 'too many points failed to transform' for remapping Geostationary to Lambert conformal?

I am trying to remap from Geostationary to Lambert conformal using gdalwarp. My input data is in netcdf, and is in geographic coordinates (degrees) and I would like to output the remapped data to ...
5
votes
0answers
304 views

Constructing a Voronoi diagram using a complicated travel time metric

I have in my possession four sets of shapefiles: 1. Locations (points), around 1000 2. Roads (lines), each road has a speed attribute 3. Terrain (polygons), each zone also has a speed attribute 4. ...
5
votes
0answers
100 views

Estimation of values for unsampled points

I want to measure biomass on a coastal mudflat. I can only access points inside the polygon. Are there any methods available that would allow me to estimate values of the points outside of the ...
5
votes
0answers
237 views

How to write an address search plugin?

I am migrating some users from MapInfo to QGIS, and before they sign off on it, they want a very simple address search in the same way that we currently have one working in MapBasic. I;ve been having ...
5
votes
0answers
967 views

Why is GDAL ECW compression much poorer than ECW compression from ERDAS

We use ECW compressor shipped with ERDAS Imagine to export Orthoimagery for our different departments. Because we are facing problems with the Imagine license server, we had to choose GDAL (built with ...

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