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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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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How do I get the pixel value of a GDAL raster under an OGR point without NumPy?

I am working on a computational model of the abundance of wild pollinators across a landscape. The model itself is complete, and I am now struggling with a post-processing step. I have my GDAL ...
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Clipping raster with vector layer using GDAL

I have installed GDAL using the Osgeo installer. How can I clip a raster layer with a vector layer programmatically? Is there any GDAL API available which can help me with this? I am using Python.
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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 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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514 views

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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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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What is the proper syntax and usage for ArcGIS “in_memory” workspace?

I am unclear how best to use the in_memory workspace in ArcGIS. The best resource I have found on the subject is from ESRI on Using in-memory workspace. Unfortunately, the help section is not very ...
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Obtaining extent of each polygon in shapefile?

In arcgis 10 and python I want to get the extent (xmax, ymax, xmin, ymin) info of each of the polygons in a shape file. I can get the extent of the whole shape file using ...
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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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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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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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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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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 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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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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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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How to run a simple python script for QGIS from outside (e.g. Sublime Text)?

I would like to run a few small and simple python scripts for QGIS (Mac) from "outside" of QGIS. With outside I mean in this context, either the normal os command line (terminal.app) or even better, ...
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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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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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328 views

Arcpy adds erroneous interior ring when writing adjacent, multipart geometry

I've run into an odd issue when using Arcpy to write multipart geometry to a shapefile. I am using an InserCursor to create a multipart feature from a list of parts each with a list of vertex pairs. I ...
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How to develop GUI in Python for geoprocessing?

I want to develop GUI in Python for geoprocessing, but I don't know what is the best GUI tool or library (Tkinter, PyQT, wxPython) for geoprocessing? Can I use PyQT for GUI programming in ArcGIS?
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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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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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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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763 views

Why learn/use Python Toolboxes over Python Script Tools?

I've written a few Python Toolboxes (which are new at ArcGIS 10.1), but am yet to decide whether/when I should write them rather than Python Script Tools in a standard toolbox. I thought the Online ...
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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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Best method to re-compile a Python Addin after editing script?

I have been developing a few python addins and I'm just wondering what is the best way to re-compile the addin anytime I edit the script. Currently, if I make an edit to the script, it seems like I ...
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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 manually break statement execution in python console 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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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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376 views

File Validation using ArcPy

I have a script which scans a directory and outputs basic raster data information such as the file name, format, number of bands, and etc. I need a way to make it so if the directory does not contain ...
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1answer
293 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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How to split shapefile per feature in Python using GDAL?

is it possible to split a shapefile per feature in python? (best would be a solution where i can temporarily save the resulting vector objects to the memory instead to disk). The reason: I want to ...
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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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323 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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How can I display raised error messages to the user in the ArcGIS geoprocessing results window?

Question: Can print statemnts raised from a custom exception be displayed in the gp results window? Background: I modified a script that I found that takes two inputs from a user, finds the ...
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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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Teaching Python to Land Surveyors

Does anyone have any good examples of using Python to automate or simplify common surveying tasks? I'm teaching a Python/ArcPy lab this week for a GIS class. There are a number of surveying ...
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Exporting arcgis features with attachments, for outside ArcGIS

Arcgis 10 features the new ability to add attachments to individual features to feature classes stored in a geodatabase. One use of this would be to add multiple pictures to a specific location, fire ...
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How could I rate roads for scenic drives?

relative GIS newbie here. I've been working on a personal project to rate roads on how nice a ride they'd be on a motorcycle. I wrote a Python program to work through road data in the TIGER dataset ...
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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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Full list of ISO ALPHA-2 and ISO ALPHA-3 country codes

I'm searching for a full list of countries with their country codes. Like on this page (need full and valid): http://www.nationsonline.org/oneworld/country_code_list.htm Thanks.
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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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Converting projected geoTiff to WGS84 with GDAL and Python

Apologies if the following question is somewhat stupid, but I am only VERY new to this whole GIS thing. I am trying to convert some projected geoTiff images to WGS84 using gdal in python. I have ...
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How to read an 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 ...