Python is an open source interpreted programming language used in many GIS programs.
58
votes
5answers
7k views
How do I access ArcObjects from Python?
I want to be able to script some things that aren't exposed via arcgisscripting or ArcPy. How do I access ArcObjects from Python?
I'm working with ArcGIS Desktop 9.3.1 right now, but will be ...
23
votes
4answers
2k views
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 ...
27
votes
9answers
10k views
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 ...
14
votes
3answers
1k views
Port “Producing Building Shadows” Avenue code to ArcGIS 10
Whuber provided an answer here Producing building shadows? which required using Avenue code. Any idea how to make it work in Arc 10?
Thanks in advance.
16
votes
1answer
3k 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 ...
5
votes
3answers
2k 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 ...
4
votes
3answers
1k views
How do I include a variable in the where clause of arcpy.Select_analysis?
I am trying to loop through a shapefile, selecting each feature in turn and copying it to a temporary shapefile to by included in a union analysis. I'm using a cursor to find the ID name for each ...
29
votes
7answers
3k views
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 ...
10
votes
3answers
4k views
list all feature classes in GDB, including within feature datasets
From python how can I build a list of all feature classes in a geodatabase, including inside feature datasets? The standard example only lists FC's at the top level of the gdb:
import ...
8
votes
3answers
4k 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 ...
12
votes
5answers
4k views
How to get the extent of each polygon in a 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
...
5
votes
3answers
3k views
Define Workspace for SDE Connection in Python
How do we define SDE Connection for workspace in Python Scripting. Its urgent please need your suggestion. Thanks
6
votes
3answers
3k views
Programmatically start and stop map services with Python
Is it possible to programmatically stop and start ArcGIS Server map services using Python?
12
votes
4answers
4k views
How to add an attribute field to an existing Shapefile via Python
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 ...
13
votes
6answers
4k views
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 ...
6
votes
4answers
1k views
How to create arcs between two points in Python?
I've been working on an python script automating the visualization of live point data. I have a table with two coordinate pairs. I'd like to connect these two point with an arc of a circle or similar ...
8
votes
3answers
2k 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 ...
10
votes
5answers
602 views
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 ...
9
votes
1answer
253 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
2answers
1k views
How to add automate values to attribute field?
I have parcel, Buildings layers, without any information attribute table, and i want to replace "NULL" values with numbers form 1 to 2000, in "Parcel ID", or "Building ID" field
thank you.
3
votes
1answer
373 views
ArcObjects + comtypes at 10.1
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 ...
17
votes
8answers
620 views
What are some resources for learning Python and 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?
31
votes
9answers
2k 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 ...
14
votes
9answers
1k 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 ...
12
votes
4answers
614 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 ...
6
votes
3answers
3k views
Arcmap: attach python script to a button?
In ArcMap 9.x how can I attach a python script to a button?
7
votes
2answers
475 views
Can ArcGIS and OSGeo4W share the same python install?
I don't like unnecessary duplication. Is it possible to install python only once and have both ArcGIS and OSGeo4W use it?
4
votes
3answers
1k views
ArcMap/ArcObjects - Drawing graphics onscreen: Explanation or tutorial for Draw/Refresh/PartialRefresh methods?
I find myself woefully lacking in understanding of when, why, and how (which type) to do screen draw/refresh/partial refresh. For instance, in a standalone Python script outside the application ...
12
votes
5answers
683 views
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 ...
10
votes
5answers
2k 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 -- ...
6
votes
1answer
116 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!
...
2
votes
1answer
136 views
Help with Python script for exporting mxds into pdfs!
I have written a python script to export my mxd into a pdf (not using data driven pages). I am getting the error that my mxd path is incorrect! I have included my script below. Any help would be ...
2
votes
0answers
428 views
Spatial Analyst Cell Statistics seems to give the wrong answer in ArcGIS 10.0
I have a script that calculates standard deviation for a list of grids using the Cell Statistics function in Spatial Analyst for ArcGIS 10.0 The syntax is this:
stdevGrid = ...
10
votes
2answers
2k views
Add a new group layer with python ArcGIS 10
Does anyone now how to add a group layer with python
can I use arcpy.mapping.AddLayer but surely this is only for an actual layer as opposed to a group layer.
so far I have this
import arcpy
mxd = ...
8
votes
3answers
4k views
How to create a shapefile in ArcGIS 10 using arcpy?
How can I create a shapefile using Python in ArcGIS 10?
I have lat & long. From this I need Python code which will create a shapefile and display it in ArcGIS 10.
Thanks.
7
votes
1answer
452 views
How to perform a table look-up using Python in ArcGIS 10.0?
Using ArcGIS 10.1 the arcpy module has a TableToNumPyArray command, which converts a table into an array.
Unfortunately I don't have access to 10.1 on my work PC. Is there a workaround which will ...
7
votes
4answers
3k views
How to remove a feature layer in an ArcPy Script
So, I have an arcpy based script where I'm trying to intersect two layers where one layer must have its centroid in the other layer. Since I need to know that one layer (feature_layer below) includes ...
6
votes
2answers
2k views
Basic Field Calculator Python Question
I'm trying to used the Python syntax in ArcGIS 10's field calculator and am thoroughly confused. So far the most basic calculations are failing me, and I don't understand why.
I'm trying to create a ...
6
votes
2answers
2k views
How should I use GDAL to perform a transformation?
Greetings,
I am a student who wishes to use GDAL to transform a series of images from Lambert Conformal Conic (EPSG: 9802) to Google Earth's WGS 84 (EPSG: 4326) for a web mapping project. I know ...
3
votes
1answer
392 views
Get a pixel value
How can i do this operation:
I want to get a pixel value fro the satellite image (Landat, GeoTIFF, 7 bands) using qgis-python.
What operators should i use? (for example in qgis's Python Console)
...
9
votes
1answer
441 views
Arcobjects in Python: assign interface to objects with feature (shape) geometry
I am trying to use ArcObject in Python. I do have problem with assigning an interface (i.e. IZ.InterpolateZsBetween) to my object with geometry data, code is:
from Comtypes.client import ...
4
votes
3answers
901 views
Select features by attribute if in Python list
I believe this will amount to largely a sql syntax question. Essentially, I am trying to complete a select by attribute in Python but based on the query of whether an attribute is present in a list.
...
4
votes
2answers
405 views
How to check if domain already exists?
I am trying to check the existence of domains in my file geodatabase which contains 4 domains (automatically populated after I created some annotation feature classes). My code is as follows:
import ...
3
votes
2answers
3k views
Can I use python 2.6 with ArcGIS 9.3?
Is it possible to use Python 2.6 (or 2.7?) with ArcGIS 9.3?
The official stance is no, not supported. There are a number of reports in the wild though that it can be done. How is this accomplished? ...
15
votes
9answers
2k 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 ...
8
votes
3answers
2k 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.
12
votes
5answers
3k 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 ...
9
votes
1answer
435 views
How to get the size of a 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 ...
13
votes
3answers
3k views
What's the easiest way to install 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 ...
9
votes
1answer
495 views
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 ...
