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

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Writing numpy array to raster file

I'm new to GIS, and I'm lost with something I feel ought to be relatively simple. I have some code that converts infrared images of Mars into thermal inertia maps, which are then stored as 2D numpy ...
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The best language to program with GDAL

I'm going to start to create programs to handle geographical data from a PostGIS server, and going to use GDAL. According to your experience, with the best language to program with it? I can program ...
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How to buffer in pyQGIS?

I'm looking for some examples to do simple python scripts in QGIS. How would I do a buffer analysis on a dataset? I can't seem to find much in the manual and QGIS python that quite matches the Esri ...
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Can i use ArcPy to get layer symbology?

Hello all Since ArcGIS 10 comes with ArcPy package, i'm wondering it is possible to use ArcPy functions to get Symbology (i.e color, width...) of a layer? Thanks in advance
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How can I iterate over map layers in QGIS python

I'm having trouble figuring out how to iterate over map layers. I can access the currently highlighted layer in the table of contents via iface.activeLayer() but I want my code to operate on all ...
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What tools in Python are available for doing great circle distance + line creation?

I need to use Python to create a great circle distance -- both a number, and preferably some kind of 'curve' that I can use to draw in a client-side map. I don't care about the format of the curve -- ...
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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 ...
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Is there Python library (other than ArcPy) for geoprocessing such as buffer?

Excluding ArcPy, is there any python library which can do geoprocessing, such as buffer/intersect, with shapefiles?
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Porting Avenue code for Producing Building Shadows to ArcPy/Python for ArcGIS Desktop? [duplicate]

Whuber provided an answer at Producing building shadows? which required using Avenue code. Any idea how to make it work in ArcGIS Desktop 10?
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Python module to delete SHP features (without Desktop GIS installed)

I have a piece of software (not Arc) that runs nightly on a non-production machine which updates shapefile features from an external database. Periodically I would like to delete all of the features ...
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How to manually break statement execution in Python window of ArcMap?

How does one break the execution of a long-running process in the python console of ArcMap? For example, how do you break a long iteration like the one below once it is started? for i in range(1, ...
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Working as a Python Development Project Team with ArcGIS?

We have a development project in Python (ArcGIS 10). This project involves a mixture of toolboxes, map templates, layer files, file geodatabase templates (acting as templates being imported into a ...
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Pure Python Library for Geometry Operations

Does anyone know of a pure Python (no C or Java dependencies) library for doing geometry operations such as buffer, union, intersects, etc? I'm looking for something that Google AppEngine compatible. ...
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Ecological geospatial conundrum

I am looking for a different, more elegant solution to a spatial statistics problem. Raw data consists of an x-y coordinate for each individual tree (i.e. converted to a point .shp file). Although ...
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2answers
889 views

How is the data access cursor performance so enhanced compared to previous versions?

The data access module was introduced with ArcGIS version 10.1. ESRI describes the data access module as follows (source): The data access module, arcpy.da, is a Python module for working with ...
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How to list feature classes with active “attribute domains”?

I have an Esri file geodatabase with attribute domains defined. I need to delete some of the attribute domains but can't because "The domain is used by an attribute rule.". How might I discover which ...
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How to get size of file geodatabase feature class on disk?

Is there a simple way to determine the amount of hard drive space a feature class takes up? I feel like I'm missing something simple, but I don't recall a method that does so. You would think that ...
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Is there a Python Lib for requesting WMS/WFS and saving as image/PDF?

i am wondering whether there's Python open-source GIS lib which has APIs to support call WMS/WFS from another GIS server (e.g., GeoServer) and then save the response data(WMS Basemap and WFS layer) as ...
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How to smooth/interpolate a raster in python using GDAL?

This is my first post so please feel free to critique where necessary. Background: I am developing in Python and using GDAL from OSGEO to manipulate and interact with rasters and shapefiles. ...
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Python is only using one core at a time to work

I noticed recently that python is only using one core at a time to work. Is there a way, maybe special builds or commands, to make it use all resources (second core)?
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How to programatically check for a mouse click in QGIS

I want to know how to check for a mouse click in QGIS. I am trying to write a python plugin and want to provide functionality similar to the "Select Single Feature" tool that already exists in QGIS. ...
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1answer
483 views

Watermarking photos using their geotag and create a shapefile

I have geotagged photographs and I would like to place a watermark of the photos location on the front for easy reference as well as creating a shapefile from the coordinates. Does anyone know of any ...
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How to use GDAL with PyPy?

I am trying to optimize my python code using pypy. While I am able to import most libraries and run succesfully, I am not able to import GDAL libraries. The same libraries when imported in Python 2.7 ...
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How to access feature classes in file geodatabases with Python and GDAL?

I am trying to access a vector dataset in a ESRI File Geodatabase using Python + GDAL. I have successfully compiled GDAL with the file geodatabase API. The FileGDB driver is working correctly since ...
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How to find and merge duplicate points?

I have two point shapefiles: Red and Blue. Each point shapefile has a z value which represents a radius (i.e. represented as buffers in the example). A duplicate point is defined as a point that ...
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How to have a python script self terminate in ArcMap10?

I have tried sys.exit, but it doesn't seem to work in ArcMap. Anyone know how to do it?
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Is there a way to access QGIS plugins in Python?

Is there a way to access QGIS plugins in Python? I'd like to write a script to do some geoprocessing, and I'd like to use the clip, regular points and convex hull tools in fTools, as well as the Road ...
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Multiprocessing Errors - ArcGIS implementation

I was wondering if anyone else in the community here has attempted to use multi-processing for spatial analyses. Namely I am trying to iterate through a series of rasters, create a multiprocessing job ...
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Creating nanoscale DEM with GDAL

A bit of a strange question perhaps, but let me give you a breif explanation of the background before my actual questions: Atomic force microscopy (AFM) is a method that, in short (and to my limited ...
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How can I utilize NumPy arrays to optimize big data geoprocessing?

I'm interested in learning how to utilize NumPy arrays to optimize geoprocessing. Much of my work involves "big data", where geoprocessing often takes days to accomplish certain tasks. Needless to ...
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How to convert projected coordinates to lat/lon using Python?

I assume this is a basic question but I can't seem to find or recognize the solution. This site returns Point: X: -11705274.6374 Y: 4826473.6922 when you searching with the first key value of 000090 ...
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How can I programmatically get the path of “Python.exe” used by ArcMap

I am working with an add-in of ArcMap in c#. From c# code, i have executed some python scripts. Now, to run those script, I have hard-coded python path. But this is not portable. So, I want to get the ...
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Determining min and max values in an ASCII raster dataset using Python?

I have a raster dataset in ASCII format. Using Python, I need to determine the min and max values inside the dataset. I've been told that the header information is key, which contains things like ...
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Smallest GIS library for embedded devices?

I need to use very simple geometry operations (read SHP or other standard format and simple searches) within an embedded device running a simple linux based os. What is the smallest and simplest API ...
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Looking for a pythonic way to calculate the length of a WKT linestring

I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
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Industry-based examples of using Python in geoprocessing and arcpy

I was asked recently by some students what types of operations GIS Analyst/Developer are usually trying to automate by using Python with geoprocessing in ArcGIS and ArcPy site package. I guess it ...
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Is it possible to get the EPSG value from an OSR SpatialReference class using the OGR Python API?

When reading a layer from a OGR PostGIS connection I can get the SpatialReference of the layer, but is it possible to get the EPSG value? Is there any documentation on this? For example: lyr = ...
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Mirror of Michigan State University's Python geoprocessing course materials

Been learning geoprocessing with Python using MSU's GEOG 825 ( python geoprocessing ) course. Unfortunately the link is dead now. I know this is a long shot but does anybody have a copy of the ...
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How to implement value-by-alpha map in GIS?

I've been doing some background reading about cartograms recently and stumbled upon interesting alternative - value-by-alpha maps. Concept is described in more details here and full paper is ...
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Efficiently finding the 1st order neighbors of 200k polygons

For every one of the 208,781 Census block groups, I'd like to retrieve the FIPS IDs of all of its 1st order neighbors. I have all the TIGER boundaries downloaded and merged into a single 1GB ...
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Measuring Script Writing Competency

I've been asked by my manager to come up with some sort of competency measure for an employees understanding of scripting/programming. Because I am a self taught programmer, I really don't have a ...
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Is there a way to use “Select by Attribute” in QGIS using a python command?

is there a way to use the function "Select by Attribute" in QGIS using a python command? In my plugin the user should enter a value via a GUI and this value should be used in a function which selects ...
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1answer
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Python increasing the filesize of my .mxd

I have a geoprocessing script that runs the following.. arcpy.AddMessage("TEST...") Yes just one line of code. A blank .mxd starts at 391kb for me as I run my script and save the filesize ...
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How to export only certain columns to a CSV file in ArcGIS?

I've written a python script using arcpy which outputs a polygon feature class into a File Geodatabase. I have added a function to export the attributes to a separate CSV file. I am using the code ...
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What software to use for making digital elevation models from UAV aerial imagery?

I have a an unmanned aerial vehicle (UAV, also called a drone) and would like to use it to create a digital elevation model and orthomosaic over a smaller area (10 km2). My platform will be able to ...
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automating roof orientation detection from satellite imagery

A while ago I did a neighbourhood roof orientation survey for solar panel deployment, by visually checking each roof and marking individually whether they were south or almost south-facing. As this ...
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Clustering Trajectories (GPS data of (x,y) points) and Mining the data

I've got 2 questions on analyzing a GPS dataset. 1) Extracting trajectories I have a huge database of recorded GPS coordinates of the form (latitude, longitude, date-time). According to date-time ...
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SP1 for ArcGIS 10.1 has extension for 64-bit Python for background geoprocessing — implications for other Python use

If the 64-bit Background Geoprocessing for ArcGIS Desktop 10.1sp1 is installed how does that affect Python configuration for general use? Esri has released SP1 for the ArcGIS 10.1 product, and for ...
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how can i convert a shapefile to lat and lon boundaries?

i have a shapefile of country subdivisions and i would like to extract an array of bounding lat and lon for each division.. is it possible to do?
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How to read Excel sheet in ArcPy script?

I'm writing a python code to convert X,Y points in excel to shapefile. In this process i have toread xy points from shhet1. What is the step i have to include in my process to read data from sheet1 of ...