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

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100
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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
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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. ...
7
votes
4answers
4k views

More Efficient Spatial join in Python without QGIS, ArcGIS, PostGIS, etc

I'm attempting to do a spatial join much like the example here: Is there a python option to "join attributes by location"?. However, that approach seems really inefficient / slow. Even ...
6
votes
1answer
4k views

Problem with import qgis.core when writing a stand-alone PyQGIS script

I am trying to write a stand alone python script in windows 7 that uses qgis.core and various other qgis libraries. I have found an old question on this subject here: How to write standalone Python ...
10
votes
3answers
2k views

Cannot run standalone QGIS script

I've been trying, along with this post, to run a script in OSGeo4w Shell, outside of QGIS. But I get the following error: ImportError: No module named qgis.core I have also read the following ...
19
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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 ...
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 ...
14
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3answers
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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?
20
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2answers
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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 ...
31
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: ...
5
votes
3answers
3k views

Python, comtypes and ArcObjects: Error creating AppROT object

I am experimenting with comtypes and ArcObjects under Python 2.6.5 and ArcGIS 10 SP1. I'm using the pure Python method to wrap the ArcObjects OLBs described in this answer, but getting an error in the ...
12
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5answers
12k views

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 ...
5
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2answers
2k views

How to automatically reload raster layers if source is changed in QGIS?

How to automatically reloaded raster layer if source is changed? (The path is the same but inside source file are changes) I use: qgis.utils.iface.mapCanvas().refresh() but layer not refresh. # ...
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 ...
19
votes
2answers
14k 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, ...
19
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 ...
24
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
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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 ...
13
votes
3answers
6k views

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. ...
6
votes
1answer
2k views

How to evaluate raster calculator expressions from the console?

How can I execute from the console an expression that should be used with the raster calculator? I'm searching for something like this: qgis.someRasterCalcClass.evaluate("boh@1 + boh@2", ...
1
vote
1answer
528 views

Flatten / collapse one-to-many table and keep the 'many' attributes separate

I have a data set that contains intersection data. Each intersection node has up to 6 links which is identified by IN_LINK and OUT_LINK attributes. I want to create a new dataset that includes the ...
11
votes
1answer
7k views

How to write standalone Python scripts using QGIS?

I've been learning how to use the Python Console in QGIS using references from qgisworkshop.org. I'm familiar with writing standalone scripts in ArcGIS and want to learn how to do the same with QGIS. ...
5
votes
2answers
1k views

Guidelines for using ArcObjects from Python

By far, How do I access ArcObjects from Python? is my most read and referenced Q&A on GIS Stack Exchange. In spite of that success, it's probably one of my weakest areas when it comes to actual ...
14
votes
1answer
2k views

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 ...
6
votes
1answer
6k views

Shortest distance from point to line (big dataset)

What is the best method to calculate the distance from the nearest road for a series of address points in QGIS, having a very big dataset? (QGIS 2.0.1, Win XP) I read the answers to previous similar ...
6
votes
2answers
2k views

ArcObjects + comtypes at 10.1 and newer

Has anyone played around with using ArcObjects in Python at version 10.1? I am having all sorts of problems, such as TypeErrors when wrapping the ESRI OLB modules and AttributeErrors when attempting ...
10
votes
2answers
2k views

Inserting newlines in Rectangle Text elements via ArcPy causes overlap?

I ran across an issue the other day when I tried to use ArcPython's mapping module to edit rectangle text elements with newlines (\n) in an ArcMap document. Here's what the output looked like: ...
9
votes
1answer
5k views

How to add feature class to MXD with ArcPy (Python)? [duplicate]

I am using ArcGIS 10.1 and I am trying to add a feature class that I create to an MXD, so that I can join to it. This all needs to be done using Python. Is this possible?
7
votes
3answers
4k views

How to replace non-English characters in attribute tables using Python?

I have a few shapefiles where some of the attributes contain the non-English characters ÅÄÖ. Since some queries doesn't work with these characters (specifically ChangeDetector), I tried to change them ...
25
votes
4answers
17k 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 ...
26
votes
11answers
8k 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 ...
11
votes
3answers
1k views

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 ...
10
votes
3answers
17k views

Define Workspace for SDE Connection in Python

How do we define SDE Connection for workspace in Python Scripting?
9
votes
4answers
5k views

How to convert geometry to WKT using ArcPy?

I would like to be able to convert a single feature (or potentially many features) in an ArcGIS layer into Well Known Text (WKT) format during a geoprocessing operation using Python and ArcPy (no ...
10
votes
8answers
13k views

How to Remove return/newline (\n) character from Field using Python and Field Calculator?

I have a geodatabase table with a field that I'm trying to remove return characters (new line). I found this post (How can I remove (chomp) a newline in Python?) of how to do it, however it is not ...
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 ...
8
votes
4answers
7k views

How do I use ogr2ogr to convert a GML to shapefile in Python

I am trying to convert a GML to an ESRI shapefile using ogr2ogr utility in a python script. I have successfully installed the GDAL/OGR package via osgeo but I am now struggling to find/understand ...
4
votes
2answers
3k views

How to install 3rd party python libraries for QGIS on Windows?

How can I use 3rd party libraries on QGIS plugins on Windows? I've developed a plugin that uses rasterio and numpy for a customer, but he's having problems installing rasterio and numpy. Actually ...
10
votes
1answer
935 views

How to visualize azimuthal data with uncertainties?

I am trying to make a figure showing azimuthal data with a different range of uncertainties at each point. This oldschool figure from a 1991 paper captures the "bowtie plot" idea that I'm aiming for: ...
4
votes
3answers
5k views

Using PyShp to convert polygons in *.csv to *.shp files?

I'm converting csv data to shapefiles using the pyshp python library. What I want to do is very similar to Using the python shape library: pyshp - how to convert .csv file to .shp, except that I ...
7
votes
3answers
3k views

How to Refresh open attribute table in ArcMap using ArcPy rather than ArcObjects?

I am running the Calculate Field GP tool from the arcpy in ArcMap. When a row value is updated, it does not show up untill I use the Reload Cache tool (Table Options > Reload Cache). How do I refresh ...
7
votes
3answers
6k views

Splitting lines automatically at specific distances using ArcGIS Desktop?

I have a set of polylines which I need to split at varying distances from their starting points. In general, I'm looking for a something similar to the SPLIT function within the editor tool. There ...
7
votes
5answers
8k views

Programmatically start and stop map services with Python

Is it possible to programmatically stop and start ArcGIS Server map services using Python?
9
votes
4answers
8k views

How to Batch Clip in ArcGIS Desktop 10 using Python/ArcPy?

I've come across a few similar questions for older versions of ArcGIS, but haven't found a suitable answer for ArcGIS 10. I have two polygon shapefiles that cover a large area (e.g. an entire ...
8
votes
3answers
2k views

Python error with open layers plugin QGIS 2

I've been using QGIS for a while but since using QGIS 2 the OpenLayers plugin doesn't work for me on my home pc. (However, I have installed the same version at my workplace with success.) I have ...
21
votes
3answers
13k 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 ...
15
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4answers
14k views

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 ...
18
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 ...
8
votes
3answers
9k views

How to write Shapely geometries to shapefiles?

Can someone demonstrate a simple way to write geometry data-structures from shapely into shapefiles? I am particularly interested in polygons with holes and linestrings. It would also be beneficial to ...
18
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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.