Python is an open source interpreted programming language used in many GIS programs.

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15
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382 views

Calculating Focal Statistics for Special Neighborhood?

I'm looking to calculate focal statistics for each cell of a raster, within a neighborhood of a specified criteria. Background - I have three binary rasters, each representing a single vegetation ...
10
votes
0answers
483 views

Geotransformation for polar stereographic?

I'm currently working to import CANGRID climate data (provided as Surfer Grid ascii, ".grd" files) into ArcGIS. The grid is 95 rows by 125 columns in size.Metadata provides lat/lon of origin (lower ...
6
votes
0answers
941 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 ...
5
votes
0answers
115 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
363 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
653 views

How to get rpy2 for QGIS on OSX?

I am a new QGIS user, have installed QGIS on a Mac running Snow Leopard OSX 10.6.8 following all the instructions. QGIS seems to work well for everything other than when I boot up I get the message ...
4
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0answers
45 views

How to run a tool from Whitebox GAT in ArcGIS?

I have a series of tools that I need to run in ArcGIS to hydrologically condition my DEM, but the first step in this process is running the Breach Depressions tool from Whitebox GAT (I have found that ...
4
votes
0answers
216 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 ...
4
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0answers
155 views

Efficiently generate Voronoi layers in qgis via Python

The following python commands both appear to function when called in qgis 2.6 to generate Voronoi diagrams: processing.runalg("qgis:voronoipolygons", pointLayer, 1, None) ...
4
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0answers
123 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: ...
4
votes
0answers
75 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 ...
4
votes
0answers
177 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 ...
4
votes
0answers
215 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 ...
4
votes
0answers
395 views

Extracting x,y,z values from a postgis linestring to python using ogr

I am trying to load a postgis linestring into python (using ST_DumpPoints) and extracting x,y,z coordinates, which is working but extremely slow..and if i mean slow, i really mean it (yes, it takes ...
3
votes
0answers
59 views

How to access a deleted features attributes (before committing)

I have a signal setup for a feature deletion event on a layer: self.layer.featureDeleted.connect(self.feature_deleted) When I try and grab an attribute from the deleted feature on the slot, a ...
3
votes
0answers
59 views

Publishing a geoprocessing service that imports modules besides arcpy?

I'm trying to publish a geoprocessing service (10.2.1) that will be used to generate a PDF from a webmap using an MXD layout as a template. The problem is that if I try to import any module besides ...
3
votes
0answers
362 views

Connect to QGIS 2.6 Python Plugin function via button on custom feature form

I am trying to connect to a QGIS 2.6 Python plugin function via a custom feature form button. On my feature form, I'm attempting to do a few things : enable the updateButton only if the ...
3
votes
0answers
81 views

Lining attributes up with features when creating shapefile using PyShp?

I used the Python Module Pyshp to select particular census blocks from the Census's shapefiles and package these into a single shapefile. However when I add this data into ArcMap and right click to ...
3
votes
0answers
63 views

point feature to raster with count of unique points

I am using ArcGIS 10.1 with Python 2.7 I have a point layer with thousands of points that each hold an id value of its owner. One owner can have multiple points, meaning that points can have the same ...
3
votes
0answers
293 views

Geometric Network for Electric Utilities

I'm not expert in the use of geometric networks nor in Python scripting and I need help with the following problem. I'm using ArcGIS 10.0. I have defined a geometric network for an electric ...
3
votes
0answers
22 views

Action: Move pointfeature to other layer - Point becomes Multipoint

I'm trying to write an action that moves a pointfeature from one layer to another. It works fine until i try to save the layer with the new feature on. He says he can't save a MULTIPOINT to a ...
3
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0answers
97 views

arcpy.mapping.ExportToTIFF fails to render layer?

Has anyone else had this problem? I have an mxd file with two layers in it, one of which is fairly 'heavy' (i.e. takes a minute or so to draw). All layers are visible by default. I have the ...
3
votes
0answers
294 views

Select and copy attributes features in ArcMap using Python add-in tool?

I'm trying to add a tool to an add-in toolbar to select features from an existing feature class and copy attributes to another feature class,from point to point. TopoHeight_Field_Name='Comment' def ...
3
votes
0answers
287 views

How to convert length in Decimal degrees to meters programmatically?

I'm new to qgis and I want to find the length of some roads in a map. So I used the following code, from shapely.wkb import loads def getLength(): layer = ...
3
votes
0answers
253 views

How to use Python's subprocess module in a for loop ArcGIS?

I am new to scripting with ArcGIS. Although this might be an easy thing for those that know Python well, I haven't figured out how to use the subprocess module in a script. I actually think I'm ...
3
votes
0answers
67 views

Overriding the QGIS Feature Dialog

We are developing a QGIS plugin and would like to override the QGIS Feature Edit Form with our own Dialog. Have explored using setEditForm and setEditFormInit, but the init process appears to want to ...
3
votes
0answers
103 views

How to compute (X,Y,Z) of a point from given attributes

Is there a way to compute the geodetic coordinates (Earth Centered) of a satellite S(x,y,z). The original problem is to compute the footprint of an antenna, given the following information: ...
3
votes
0answers
146 views

Create vector grid from canvas using script

I've modified "Hex grid from layer bounds" script to my need. Just added cellsizex and cellsizey. Changed the hexagonal - 3 to "1" to make it as a square grid. Is it possible to include an option to ...
3
votes
0answers
61 views

ArcPy: Initialize zero valued grid Raster and iteratively increment

I'm jumping right into ArcPy to help out a friend who needs to automate some ArcGIS work. The problem at hand can be reduced to the following pseudocode: accumulationRaster = SomeZeroedRaster for ...
3
votes
0answers
377 views

QGIS API - Print Composer Template produces empty map?

I have a print composer template which I'm trying to populate with different subset queries from a CSV-derived vector layer using the Python API. However, all the output PDFs contain everything except ...
3
votes
0answers
77 views

How to find the minimum number of inspection points?

I am working on a pipeline inspection project and there is a high liklihood that some inspection tool deployment/retrival station will need to be installed on the pipe network. the problem is ...
3
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0answers
87 views

Arcpy in Python Plugin for SPSS

Is it possible to run the arcpy module in the Python for SPSS plugin to run the search and update cursors?
3
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0answers
136 views

PyQGIS: How to color raster layer with existing colorBrewerMap

With pyqgis I have added multiple new raster layers to the legendinterface(). Because i like the ColorBrewer style i want to color some of them with the "Spectral" gradient. How can I do this in ...
3
votes
0answers
142 views

python equivalent of spatstat's spatial point process functions

Is there a free python package (i.e. PySAL?) that implements the standard summary statistics for spatial point processes, e.g. the F, G, J, and K functions? I'm happy to use R (i.e. spatstat) if ...
3
votes
0answers
126 views

Calculate size of area where data values exceed certain limit

I am using Python and Basemap to plot sea ice concentration within the Arctic region. I need to calculate the total area (square meters) where the sea ice concentration exceeds a certain limit (e.g. ...
3
votes
0answers
213 views

Accessing existing instance of qgis from stand-alone python script

For my own data analysis pipeline, I am running a split screen setup with iPython notebooks on one side, generating variables from source data, pushing them to a csv file which qgis then reads/joins ...
3
votes
0answers
185 views

Generate tiles using GPU

I was wondering if anyone has tried already to utilise the GPU in tile generation? I have a quite big dataset so tile generation takes a while (especially on high zoom levels) even on a quite high ...
3
votes
0answers
174 views

Handling non-spatial data for QGIS projects with Camelot

Most of my projects include data which is non-spatial or which is point data and can be managed by a regular relational database. Previously I found Manifold and ms-access were a good combination ...
3
votes
0answers
356 views

Buffering a Raster with GDAL and Numpy

I am using GDAL to convert a raster dataset into a numpy.array and then using numpy to buffer the data in the raster. For example, I need to know all the regions within 100ft of a school point ...
3
votes
0answers
86 views

Is it possible to access individual pages within an existing pdf using arcpy.mapping?

I've used the arcpy.mapping module for some time now to create mapbooks and other pdf documents, using a combination of Data Driven Pages and Python. I would like to take an existing pdf and save each ...
3
votes
0answers
222 views

How to create a Typographic Map with Mapnik

So i am trying to make a typographic map using mapnik. I want the street names along a particular street not to overlap, but I want an intersection between two streets to over lap. Currently some ...
3
votes
0answers
315 views

Is there a Python WMS client (thin client analogue of OpenLayers)?

I'm making a geoportal based on (Geo)Django 1.5, PostgreSQL 9.1 + PostGIS 2.0, QGIS MapServer and OpenStreet Map or Google Maps WMS services for the base layer. It seems like there is no problem, but ...
3
votes
0answers
411 views

Configure Python with Geoserver

I am developing a WebGIS application with: Openlayers 2.12 PostgreSQL 9.2 with PostGIS 2.0 extension Geoserver 2.2.3 Apache 2.0 configured with Tomcat 7.0.35 PROBLEM One of the services of the ...
3
votes
0answers
698 views

How to write vector layer to csv file with geometry by PYTHON?

I use Python try to write vector layer file to csv file with this code QgsVectorFileWriter.writeAsVectorFormat(mylayer, r'c:\temp\xyz.csv', "utf-8", None, "CSV") It can export to xyz.csv but only ...
3
votes
0answers
415 views

Create easy Annotations from point features with python in ArcGIS 10.0

Because in ArcGIS 10.0 there is still no simple toolbox function to convert labels to Annotation, I try to go a substitude way with the callable Toolbox function [TiledLabelsToAnnotation][1] on a ...
3
votes
0answers
126 views

traversing KML files with ogr python

i'm new to OGR processing and KML format so be gentle: i've got a series of KML files all containing multiple regions partitioning a larger area in each. i also have a series of geocoded points for ...
3
votes
0answers
401 views

Importing matplotlib basemap and shapely

I'm not sure if this is the right place to ask this, but here we go. I have a python script that uses matplotlib's basemap and another part that uses shapely to do an intersection of 2 polygons. If ...
3
votes
0answers
219 views

How to merge SeaWiFS and MODIS data or use other merged products?

I hope to produce a time-series for sea surface temperature (SST) and chlorophyll-a (Chl-a) for use in MaxEnt without the use of arcgis, preferring Python tools to others. I am new to satellite data ...
3
votes
0answers
77 views

Adding points to represent non-chosen locations

I am looking for a way to set up a discrete choice model in ArcGIS for foraging behavior of individuals, in a grid of 15 locations. To do that I need a point for every possible choice they could have ...
3
votes
0answers
140 views

How to change the QGIS help dialog?

I am working with python plugins for QGIS. I am done with my one of my .py file using python 2.5 and pyqt4. It is just help file for QGIS, which i changed. I wanted to incorporate the same in QGIS. I ...