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

learn more… | top users | synonyms

8
votes
5answers
2k views

Who uses FME Python extension and how?

I saw a great interface to FME with Python What you guys are doing with it? I want ideas.
8
votes
2answers
2k views

How to access Esri ArcPy modules from Enthought Canopy?

I have ArcGIS 10.1 running on my windows system and I have also installed the new 32-bit Canopy Express Enthought Python Distribution. Is it possible to load and use the Esri ArcPy modules from ...
8
votes
3answers
5k views

How to find the locations of the highest values in a raster?

Using ArcGIS 10, I have a raster where I would like to find the pixel with the maximum value in the raster and return its location (center of pixel) in decimal degrees. I would like to iterate through ...
8
votes
5answers
1k views

Will there be a Python API for ArcGIS Server?

It seems like an obvious next step given the big push towards Python in ArcGIS Desktop at 10.0. Are there any limitations of Python compared to javascript, flex, etc that would prevent ESRI from ...
8
votes
6answers
5k views

How can I calculate the orientation of each side of a polygon in ArcGIS 10?

I want to examine the orientation of each line in a polygon so that I can calculate their solar exposure. Each polygon represents a building, and has an associated height. For the moment, I just want ...
8
votes
4answers
2k views

Best way to find the polygons crossed by a line

I'm trying to find all the polygons crossed by a single line (a GPS track). I'm using the OGR library (from python) for computing this, but it's currently a bit 'brute-force' (and slow). For every ...
8
votes
4answers
1k views

Is there a mapping between OGR and python data types?

I'm writing a shapefile using OGR in python, creating fields on-the-fly from a python data source. Creation of a new field requires an OGR data type, is there a mapping between OGR and python data ...
8
votes
6answers
1k views

How to integrate SAGA Python Modules into ArcGIS Desktop?

I have been having a look at SAGA (http://www.saga-gis.org/en/index.html) and it seems to have some nice tools for geoprocessing. I was wondering if anyone out there has had any luck bringing SAGA ...
8
votes
2answers
937 views

ArcMap running scripts slower if you import Arcpy

I am finding ArcMap runs slower, if you have written a script, which imports arcpy. You may wish to write a script that can be operated in ArcMap, through the python window, or as a standalone ...
8
votes
3answers
9k views

How to create a button in Arcmap 10 to run a Python program?

I have a script that I want to run within ArcMap when a button in a toolbar is clicked, and so far I have only been able to make the script into a script tool. I need it to run as a command, not as a ...
8
votes
1answer
706 views

Fastest methods for modifying attribute tables with Python?

A while ago, I wrote a quick Python function for converting an attribute table to a python dictionary, where the key is taken from a user-specified unique ID field (typically the OID field). ...
8
votes
3answers
477 views

Using ESRI geoprocessing services from a non-ESRI client (Python)?

I'm thinking it should be possible to consume an ESRI Geoprocessing service from a python script without invoking ArcPy or needing an ESRI installation on the client machine. For example I create a ...
8
votes
4answers
482 views

Joining lines when direction is not known

I am struggling with this problem. I have a polyline made up of several segments. Each segment is made up of points, each point identified in 3D space by coordinates and elevation. Together, if ...
8
votes
4answers
1k views

How to split single address field into 4 fields (House No., Direction, Name, Suffix)

I have to do some massaging of our parcel data to make it usable by a program in sheriff helicopters. The program requires one of the following address formats within the fields: Our addresses are ...
8
votes
1answer
688 views

How to address the new “Task-Completed” QgsMessageBar in Python?

I am really amazed what huge steps the QGIS development has taken in the last months. The new iconset, the improved Print composer and many more changes to be seen in QGIS 2.0 are really awesome! ...
8
votes
1answer
1k views

How to add a toolbar via python?

Through tutorials I learned how to add a toolbutton to the plugins-toolbar via python. Now I wonder how to add a complete toolbar with toolbarbuttons via python. Can anybody give some example-code? ...
8
votes
2answers
279 views

Migrating from ArcGIS to gdal

I would like to collect a table of equivalent or close enough gdal based functions to replace ArcGIS functions (esp in spatial analyst). Are there functions available using gdal to perform the ...
8
votes
2answers
601 views

How to create a solar intensity map for a garden plot?

I'm interested in creating a raster surface that depicts the average solar intensity per unit area for a small garden plot. I imagine the inputs into the model would be the following: Plot ...
8
votes
4answers
1k views

How to split points by polygon?

I am looking for a way to split points by a county polygon feature class. The attached image shows two feature classes: one composed of points and the other a county polygon feature class. The split ...
8
votes
6answers
970 views

How do I generate thumbnails images from lots of shapefiles?

A colleague and I recently released an Open Source project called Mapoteca which is a set of Python Scripts that integrates with a GDAL/FWTools installation allowing a full walk-through of directories ...
8
votes
5answers
6k views

update one shapefile attribute table with values from another dbf table

I try to explain here what I am trying to do: I have one shapefile and one independent dbf table with the same fields. In the dbf table all the fields are populated but in the shapefile attribute ...
8
votes
1answer
4k views

Problem with setValue() function in ArcGIS 10

I'm trying to add data to an attribute table in ArcGIS 10 using the following code: def make_floor_no( shapefile ): "Makes header for number of Floors (FLO) and calculates value" fieldName = ...
8
votes
1answer
2k views

What Lidar processing tools are available in Python?

I have been using FUSION and the command line FUSION Lidar Toolkit (LTK) to process Lidar data. A broad Google search ("Lidar Python") yielded libLAS and pyLAS as Python lidar libraries, however, ...
8
votes
2answers
285 views

Unusual results for geoprocessing speed tests

I have been observing unusual performance with a Python geoprocessing script. The (attached) script performs the following actions: Use a search cursor to look up UTM zone corresponding to polygon ...
8
votes
1answer
1k views

concurrent use of in_memory workspace in arcpy

i am using a python script that's eliminating small polygons from a feature class. this script creates temporary feature classes with fixed (hardcoded) names in the "in_memory" workspace. example: ...
8
votes
2answers
3k views

How to Rotate Features in ArcGIS for Desktop using ArcPy?

I have a series of polygons that I want to rotate. Each polygon has a rotate angle and an anchor point (xy coordinate) stored as field values. As it happens, all anchor points are on a vertex of ...
8
votes
2answers
2k views

Split a feature when intersecting with a feature of another layer using PyQGIS/Python?

I have a buffer layer (green polygon) which I want to split to two polygons whenever it crosses a barrier (blue line). I have been trying to use "splitGeometry" method, but I just can't get it to ...
8
votes
1answer
327 views

How to debug a QGis python plugin

I'm trying to write a python plugin for QGis. I'd like to debug some DB queries and I need a way to display the result. I thought about using a popup to display it, but I don't know how to show a ...
8
votes
1answer
417 views

Running ArcGIS 10.0 Under Virtualenv

I am working on a Python package that has a mixture of command line tools and ArcToolbox tools. For Python development it is really useful to use VirtualEnv, especially when working with installers. ...
8
votes
3answers
891 views

Are there any training resources in SQL and Python as applied to GIS database management? [duplicate]

I've taken ESRI database courses, which have been helpful to my work. But I also need training in SQL and Python as applied to GIS database management. There are lots of suggestions for Python ...
8
votes
2answers
204 views

Feeder bus service

First of all, a little background. I work for a regional transit agency. We are making a "diagnostic" about our feeder bus service. We'd like to know what proportion of our users could take the bus ...
8
votes
2answers
153 views

File naming for Enterprise GIS database?

I'm designing the guidelines for an Enterprise GIS database. Part of this database will include customized geoprocessing tools using a variety of software. I'm interested in knowing whether anyone ...
8
votes
2answers
4k views

Converting from DMS to DD using Python in Field Calculator?

I need to convert lat/long that is expressed as degrees, minutes, and seconds in the data into decimal degrees. For example, in the data, they are listed as N335042.06 in the Latitude column, and ...
8
votes
1answer
303 views

Python with GDAL and PostGIS as a replacement of ArcGIS

Few times ago, I worked with daily land surface temperature satellite images of an area with the size of Alaska. I had to process around one thousand images. I downloaded them, mosaiced, projected, ...
8
votes
1answer
2k views

How to make a new raster using con() script in Python?

I'm new to Python and have been trying to code a raster calculator style script. Basically, I want to convert a raster that has values 0 to -10,000 into a raster that is populated by 1s between ...
8
votes
1answer
3k views

GDAL RasterizeLayer Doesn't Burn All Polygons to Raster

I am trying to burn a shapefile to a raster using GDAL's RasterizeLayer. I pre-create an area of interest raster from a different shapefile, given a specific pixel size. This AOI then serves as a base ...
8
votes
2answers
642 views

How to catch PostgreSQL/PostGIS errors in GDAL/OGR Python bindings?

Is it possible to catch PostgreSQL output error messages in OGR after a query has failed? For example conn.ExecuteSQL('SELECT * FROM non_existing_table;') In Postgres this returns an error ...
8
votes
4answers
3k views

Python script - how to avoid exclusive schema lock error?

I have a script for updating some features on my database every night (just for copying and replacing some features). This features are "read-only". My problem is that I can't avoid that these ...
8
votes
2answers
760 views

How to write scripts that can call on both Arcpy and PyQGIS?

I have spent quite a bit of time looking for a clear answer this topic and have still been unable to really accomplish my goal of accessing PyQGIS in a stand alone script. Parts of answers have been ...
8
votes
1answer
245 views

Difference between python window and toolbox

Are there differences in performance or other potentially critical area between running a python script in the python window versus running it from the toolbox in ArcGIS 10.0? I am asking in cases ...
8
votes
1answer
2k views

Pros and cons of using Ruby/Rails/RGeo or Python/GeoDjango for a web based GIS

We're at the investigation phase of creating a web based GIS. We're assessing options for an ORM to use in all of our backend import/export and processing routines. From my research, GeoDjango appears ...
8
votes
2answers
636 views

What are mystery green lines in Layout View produced during ArcObjects script execution?

Could any of ArcObjects guru tell me, what are these green lines on my Page Layout and what to do, or not to do, so they do not appear? See image attached. I do used ArcObjects from Python. My script ...
8
votes
1answer
512 views

How to split two interscting polygons by the average linestring of the shared area (QGIS / python shapely)

I have two polygons, POLYGON((-5 -5,-5 5,5 5,5 -5,-5 -5)) POLYGON((1 1, 1 7, 7 7, 7 1, 1 1)) and wish to split them evenly. The result should be a split along the red marked line. I'm using ...
8
votes
1answer
475 views

How to see what lines have changed in an updated Shapefile?

I'm using my county's GIS data to update the roads in OpenStreetMap. I have a copy they published last year and one that was just published, and I'd like to find all the LineStrings that have either ...
8
votes
1answer
5k views

How do I maintain a resposive GUI using QThread with PyQGIS

I have been developing some batch processing tools as python plugins for QGIS 1.8. I have found that while my tools are running the GUI becomes non-responsive. The general wisdom is that the work ...
8
votes
2answers
668 views

Python script to read CAD data to find polygon extents

I have Civil 3D 2012 with ArcGIS for AutoCAD 300. I want to read the extents of a polygon in the drawing. Feature Class in A4A300 = Boundaries, the CAD layer is PROP-BNDY, there is only one polygon on ...
8
votes
2answers
2k views

Converting File Geodatabase Table to Access 2007 ACCDB table programmatically?

Does anyone know of a method to convert a File Geodatabase Table into an Access 2007 Table programmatically. I have been trying using the PYODBC library and a series of insert statements but am ...
8
votes
5answers
697 views

How to set ArcGIS for Desktop license to lower level for testing whether Python script still runs?

I have a Python script that will need to be given to a client. We are currently evaluating what license level the client will need in order to run the script for their software acquisition purposes. ...
8
votes
2answers
791 views

How to remove spikes in polygons with ArcGIS 10/Python?

In the picture below you can see a polygon layer, representing steep slopes, extracted from a TIN. The polygons have a lot of spikes in them. I would like to remove these spikes while the rest of the ...
8
votes
2answers
2k views

How to buffer a vector shapefile using ogr python?

I am trying to learn how to use ogr in python using the country and populated places datasets from http://www.naturalearthdata.com/downloads/50m-cultural-vectors/. I am attempting to use filters and ...