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

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How do I access ArcObjects from Python?

I would like to be able to script some things that are not exposed via arcgisscripting or ArcPy. How do I access ArcObjects from Python?
52
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10answers
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Alternatives to using Arcpy

I seem to use ESRI's Arcpy site package for virtually all of my python geoprocessing. To ESRI's credit, these are an incredible suite of tools that can help accomplish a great deal. However, I would ...
50
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6answers
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When to use ModelBuilder over Python scripting and vice versa?

I am new to Python scripting in ArcGIS but not new to ModelBuilder. I would like to know the benefits of Python vs ModelBuilder. When should we write Python script for GIS automation rather than ...
48
votes
14answers
16k views

Resources for learning Python programming with generic GIS goals in mind?

In your opinion, what is the best book/site to learn Python with GIS goals in mind? By "best", I mean: not very long (book) easy to understand (book/site) good practical examples (book/site) For ...
41
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11answers
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How to install GDAL with Python on windows?

Can anyone please explain to me in step by step instructions how to install GDAL/OGR with Python on Windows. I have Windows Vista and I have tried following the information on the website and it does ...
37
votes
1answer
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How to smooth the polygons in a contour map

Here is a contour map for which all the polygons of levels are available. Let ask how to smooth the polygons keeping all vertices preserved in their exact locations? Indeed the contour is made on ...
35
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10answers
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What are some resources for learning ArcPy?

I would like to learn ArcPy, but I do not know quite where to begin. Does anyone have any good advice on where I should start to learn ArcPy?
35
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7answers
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How can I effectively debug arcpy Python scripts?

I have written many Python scripts using arcpy in ArcGIS 10, and so far my only means of debugging is restricted to printing messages to the geoprocessing results window using arcpy.AddMessage(). Are ...
31
votes
4answers
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Performance of ArcGISScripting and large spatial data sets

I am currently writing a python script using the arcgisscripting module to process a reasonably large data set (~10,000 records in total) normalised over a small number of tables, 8 in total. The ...
29
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3answers
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How to Share Open Source Python Code for ArcGIS?

My company just purchased ArcGIS software. I'll be writing scripts for ArcGIS in Python. Is there a community or open source project where this code can be shared?
29
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2answers
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Streamlining Python Code for Big Data

I have Python code which is designed to take point shapefiles through the following workflow: Merge points Integrate points, such that any points within 1 m of each other become one point Create ...
27
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9answers
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How to easily shift all features in a vector dataset?

Let's say that I put together a Shapefile and all the features have their vertices shifted by a constant amount. What's the easiest way of shifting all the features (hence the (x,y) position of their ...
25
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3answers
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Simple thematic mapping of shapefile using Python?

I wish to visualize geographical data in Python, without using ArcGIS/ArcPy, and make a map. On the internet I found how to make a thematic map using Python: Here is some code that I tried: ...
23
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4answers
959 views

Recommend topics to be included in a Computer Science for Geospatial Technologies course

I will be instructing a course at the local university titled Computer Science for Geospatial Technologies. This is an introductory course meant to introduce computer science concepts to geospatial ...
23
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5answers
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OpenSource Remote Sensing Tools for Classifying Roofs

with envi image processing and classification tools, you can get roofs from images with some spectral value and then you can convert it some vector data for your app. in python with OpenCV which have ...
22
votes
10answers
8k views

How do I develop my GIS programming skills?

I would like to develop my GIS programming skills, where do I start? People say learn C++ or Python but where can I learn this in a geographic context? Tutorials or anything would be very helpful, as ...
22
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2answers
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Python Efficiency — Need suggestions about how to use OGR and Shapely in more efficient way

I'm looking for some suggestions about how to make my python code more efficient. Normally efficiency doesn't matter for me but I am now working with a text file of US locations with over 1.5 million ...
22
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1answer
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What does the adoption of Python by NVIDIA for GPGPU mean for GIS?

Today NVIDIA announced support for the Python language on its flavor of GPGPU (CUDA). Manifold GIS uses CUDA to enable some accelerated raster operations but it is not a programmable environment and ...
21
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4answers
9k views

Python Script examples for geoprocessing shapefiles without using arcpy

I would like to use a Python script that is not based on arcpy to do things like query a shapefile by attributes, create new layer from selection, and calculate areas of a polygon and convert ...
21
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8answers
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Value of a Python programming course

I am considering upping my programming skills by taking a python geoprocessing course through ESRI. Before I part with the hefty registration fee, I would like to get your opinion on the value of 24 ...
21
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7answers
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Nearest neighbor between a point layer and a line layer

I've asked this question several times on stackoverflow and irc between #qgis and #postgis and I also tried to code it or implement it my self in postgis with no real answer. Using programming (most ...
21
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6answers
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How to buffer raster pixels by their values?

The pixels to the left represent tree locations and their associated crown radii (i.e. pixel values ranging from 2 - 5). I would like to buffer these raster pixels by their crown radius value. The ...
20
votes
11answers
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What are the Python tools/modules/add-ins crucial in GIS?

With ArcGIS 10, Python has become the de-facto scripting language for ESRI. While leading Open source software like QGIS, GeoServer, PostGIS all supports Python. Thus it became important to know/learn ...
20
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6answers
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Defining projections for multiple shapefiles in ArcMap?

I have over 100 shape files that don't have .prj file and thus when I bring them into ArcMap 10 they show the coordinate system as unknown. I know all of the shape files coordinate system is GCS WGS ...
20
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4answers
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Run a Python Script when opening an MXD?

Can anyone tell me how to accomplish this? I want a Python script to run on opening the MXD which would pull an excel worksheet into a GDB and refresh the map. I only want this to happen in this ...
19
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5answers
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How to use ArcGIS functionality in Python without running ArcMap (e.g. separate editor/environment)

I'm trying to take the next step in programming ArcGIS with Python and see if its actually possible to run my script/code without having to load ArcMap and paste them into the Python window. I imagine ...
19
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6answers
585 views

Python for GIS on a thumb-drive

I'm looking at putting together a light Python install on a thumb drive that I can take to client offices and do some basic GIS processing. I'm thinking of installing the following: PyScripter ...
19
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3answers
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How to call gdal_translate from Python code?

Is it possible to use some gdal API to call gdal_translate from Python code? I do not mean simply executing the gdal_translate.py from the file system, but rather call it somehow in code so I do not ...
18
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9answers
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Is there a way to code-complete arcpy scripts using an external editor?

I have been scripting in Python for ArcGIS 10, and so far I have just been using Notepad++. I like how the Python command line interface code-completes arcpy functionality for you, showing you your ...
18
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3answers
908 views

Is it possible to look at the contents of Shapefile using Python without an ArcMap license?

I wondered if it is possible to look at the contents of a shapefile using Python without having and ArcMap license. The situation is that you can create shapefiles from many different applications, ...
18
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3answers
373 views

Python literature relevant to QGIS

Python for ArcGIS is a book that I have been looking at. Does anyone know if this would be applicable in QGIS? I am not looking to write application/plugins, simply get better at understanding ...
18
votes
3answers
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ArcPy and running Python scripts (with parameters) within another Python script

A common coding pattern used in AML was to run an AML (with parameters) inside another AML. An application that I'm currently developing would benefit from being able to run a Python script (with ...
17
votes
4answers
9k views

How to add attribute field to existing Shapefile via Python without ArcGIS?

I have a Python script that adds an attribute field to a Shapefile if doesn't exist. This is easy to do with ArcGIS (graphically or via Python), but I'm looking for something that doesn't depend on ...
16
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6answers
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Generate points that lie inside polygon

I have polygon feature and want to be able to generate points inside it. I need this for one classification task. Generating random points until one is inside the polygon wouldn't work because it's ...
16
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2answers
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How to divide a polygon into specific sizes using ArcGIS?

I have several thousand irregularly shaped polygons in a shapefile. I want to be able to split each polygon into three areas, and to specify what the size of those areas (they sum to the previous ...
16
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5answers
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How to make a GIS inventory?

My office will be seeing a big change in its GIS section. This section has been operational since the 1980's and has a huge collection of GIS data (i.e., shapefiles, raster files, data, etc) but never ...
16
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5answers
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How are people using Python data structures and classes in ArcPy?

This question may expose my ignorance on programming but I'm curious about how people are using different python data structures within ArcPy. This page lists the data structures in Python. I ...
16
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1answer
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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 ...
16
votes
2answers
9k views

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, ...
16
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2answers
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How to find the angle between intersecting features in two featureclasses?

I have two intersecting line featureclasses. I want to find the angle at each point of intersection using ArcGIS 10 and Python. Can anyone help?
16
votes
1answer
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Voronoi polygons that run out to infinity

I have been working on implementing the voronoi.py script (Bill Simon's translation of Steve Fortune's code). According to the QGIS link it is basically the same code that I am working with, but the ...
15
votes
4answers
2k views

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 ...
15
votes
6answers
6k views

ArcMap 10.0 Python Field Calculator, Find/Replace Double Quotes

I'm trying to use the Field Calculator (ArcMap (10)) to strip out double quotes in an address field (I didn't put them in there, believe me). I've tried many incantations but am still unable to even ...
15
votes
3answers
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Listing all feature classes in File Geodatabase, including within feature datasets?

From python how can I build a list of all feature classes in a file geodatabase (*.gdb), including inside feature datasets? The standard example only lists feature classes at the top level of the ...
15
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3answers
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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 ...
15
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4answers
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Is it possible to use Arcpy in ArcGIS 10 to zoom to a selected feature?

The answer to this may be a simple yes or no, but I'm hoping that someone is aware of a way to zoom to the extent of a selected feature using the ArcPy modules in ArcGIS 10.
15
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4answers
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What python web-mapping framework to use?

I am interested in developing a web-mapping application. I am relatively familiar with Python and so i'm looking for a python framework. What are my options? what are the pros and cons of each option? ...
15
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6answers
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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 -- ...
15
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3answers
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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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Python GDAL package missing header file when installing via pip

I asked this question on Stack Overflow before I realised this site existed. As this site it more appropriate, I'll ask it here too. I'm trying to install gdal from pip pip install gdal inside a ...