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

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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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3answers
787 views

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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1answer
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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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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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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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3answers
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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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1answer
524 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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1answer
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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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1answer
437 views

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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1answer
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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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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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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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1answer
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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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1answer
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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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5answers
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Recommended programming language for remote sensing?

I am beginning studies that hopefully will lead to a long career as a remote sensing specialist. I am currently working with ArcGIS for some applications and learning ENVI for others. I have ...
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3answers
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How to convert geoJSON to python objects?

New to the site, and to geoJSON, and to python. My goal is to read in a file with geoJSON data, and use it to generate shapes to be used in an application that is using python scripting. Python has ...
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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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2answers
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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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How to change feature class and field aliases in bulk?

I have over a hundred FCs, each with 10 or 20 attributes to add or change the aliases for, two or more times a year. Needless to say, this is not something I'm going to grunt my way through. How can I ...
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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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5answers
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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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2answers
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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 ...
12
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3answers
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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 ...
12
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1answer
392 views

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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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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2answers
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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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1answer
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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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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 ...
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2answers
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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 ...
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How to fully load a raster into a numpy array?

I have been trying to check my filters on DEM raster for pattern recognition and it is always resulting in missing last rows and columns(like..20). I have tried with PIL library, image load. Then with ...
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4answers
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Get all vertices of a polygon using OGR and Python

I'm having a little trouble with the Python OGR API. What I am trying to do is get all the coordinates of each vertex of the outer ring of a polygon. This is what I have so far: import osgeo.ogr ...
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2answers
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Methods for optimizing multcore processing in ArcGIS

I am interested in learning methods to utilize the full extent of multicore processing power available on a desktop computer. Arc states that background geoprocessing allows the user to utilize ...
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1answer
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GDAL/Python: How do I get coordinate system name from SpatialReference?

In Python, using GDAL, I've extracted a raster's projection as a WKT string as follows: wkt = dataset.GetProjection() # wkt is ...
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1answer
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Polygon overlay with Shapely

I'm trying to capture all the non-overlapping polygons indicated below using Shapely (given polygons A,B & C). Moreover, I'm hoping to do so without iteration, testing for intersect etc. The ...
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3answers
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How can I parallelise embarrassingly parallel GIS operations in QGIS python?

A common requirement in GIS is to apply a processing tool to a number of files or apply a process for a number of features in one file to another file. Much of these operations are embarrassingly ...
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Is there a way to refresh imported modules in a ArcGIS Python Toolbox?

When using a python toolbox (.pyt) in ArcMap, I'll typically follow a pattern where the .pyt file itself is simply a wrapper to collect input arguments and define the tools themselves. Supporting ...
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How to convert LAS file to numpy array?

I have begun learning how to manipulate LAS data in python and wanted to see how others handle LAS files. I would like to read the points (I am using a numpy array), and filter out classes 1 and 2 ...
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How to get raster corner coordinates using Python GDAL bindings?

Is there a way to get the corner coordinates (in degrees lat/long) from a raster file using gdal's Python bindings? A few searches online have convinced me that there is not, so I have developed a ...
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4answers
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Programatically splitting polygon with line?

In looking at this question, it occurred to me that I am not sure how one would go about using geoprocessing tools in ArcGIS to split a polygon with a line programatically. Manually, you would use ...
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2answers
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How do you delete an in-memory Table View?

In a Python script, I'm cycling through thousands of Excel files and using arcpy.MakeTableView to create in memory table views from the first spreadhseet in each file. How do you delete the reference ...