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

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99
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5answers
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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?
62
votes
12answers
48k views

Installing GDAL with Python on windows?

Can anyone explain 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 not seem to bind the exe files for me. ...
54
votes
10answers
5k views

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 ...
49
votes
15answers
22k 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 ...
42
votes
3answers
8k views

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 ...
30
votes
3answers
13k views

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: ...
28
votes
9answers
3k views

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 ...
26
votes
11answers
7k views

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 ...
25
votes
4answers
16k 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 ...
25
votes
10answers
10k 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 ...
25
votes
6answers
1k views

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 ...
23
votes
6answers
19k views

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 ...
23
votes
4answers
1k 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
votes
2answers
4k views

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 ...
23
votes
7answers
10k views

Nearest neighbor between point layer and 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 ...
23
votes
5answers
4k views

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 ...
23
votes
3answers
10k views

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.exe from the file system, but rather call it somehow in code so I do not ...
22
votes
8answers
2k views

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 ...
22
votes
1answer
1k views

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 ...
20
votes
3answers
12k views

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 ...
19
votes
5answers
4k views

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
votes
3answers
3k 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, ...
19
votes
1answer
8k views

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 ...
19
votes
6answers
613 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
votes
2answers
13k 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, ...
18
votes
12answers
21k views

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 ...
18
votes
3answers
18k views

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 ...
18
votes
3answers
387 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
2answers
7k views

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 ...
18
votes
2answers
5k views

How to make a separate Python installation that can call ArcGIS' arcpy?

I see a lot of threads asking how you can create a separate Python installation (e.g. the Anaconda or Python XY distribution) that can use arcpy, while not 'breaking' the original ArcGIS python ...
18
votes
3answers
11k views

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.
18
votes
8answers
18k views

Installing GDAL and OGR for Python?

I am developing some code in Python, and I want to use the GDAL/OGR python bindings. What is the minimum I need to install in order to use the GDAL and OGR python bindings? What is the easiest way to ...
17
votes
6answers
9k views

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 ...
17
votes
4answers
5k views

What python web-mapping framework to use? [closed]

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? ...
17
votes
4answers
11k 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 ...
17
votes
2answers
5k views

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?
17
votes
1answer
3k views

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 ...
16
votes
12answers
45k views

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.
16
votes
4answers
4k views

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 ...
16
votes
5answers
2k views

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
votes
3answers
8k views

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 ...
16
votes
6answers
6k views

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 -- ...
16
votes
1answer
625 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 ...
15
votes
4answers
2k views

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?
15
votes
3answers
9k views

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 ...
15
votes
4answers
3k 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
2answers
790 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 ...
14
votes
4answers
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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 ...
14
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3answers
3k views

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?
14
votes
4answers
2k views

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 ...