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

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Best design for Open Source Python / PostGIS prototype

I am writing a data intensive web application that is delivered through apache. My question is about how to best arrange processing given that there are multiple options. I have at my disposal ...
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1answer
2k views

Importing GDAL from Python window of ArcGIS for Desktop?

I am trying to run some Python code using the Python window in ArcGIS 10.1 that uses both the arcpy and gdal modules. However, when I try and import the gdal module I get an error: ImportError: No ...
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2answers
625 views

Generate near table for x number of neighbours using arcpy

There are 3 likely scenerios that I am trying to capture near distances for: An interchange subway station, which has 2 or more neighboring stations. That is, the station in question connects 2 or ...
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4answers
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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 ...
9
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1answer
6k 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 ...
9
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2answers
871 views

Scriptable alternative to ArcScan (particularly vectorising lines within tolerances)?

Sadly the answer to Can you access ArcScan from a python script? suggests that it is not possible to script ArcScan from within a python script. Therefore, does anyone know of any alternatives to ...
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1answer
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automated georeferencing

I am attempting to fully automate the process of georeferencing a load of .png files - i have xml file containing the co-ordinates - but how can i use them? Does anyone have any advice?
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1answer
535 views

How to call the interpolation plugin from the python console?

I would like to call the QGIS interpolation plugin function (TIN method) (Raster->Interpolate) from python console. I can't find the corresponding function within QGIS API or within the ...
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1answer
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How to prompt for user input during ArcGIS Python script tool execution?

I want to prompt for user input after all parameters have been specified for the script tool. I've seen many forum posts and stackexchange questions about this, and they all conclude that it's ...
9
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1answer
928 views

Arcmap Select by Attribute with Python

I would like the following to select (highlight) the "project" layer that intersects the grid, and then pull a record from the selected "Grid". I do not need to save the layer. Note: Running the ...
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Python/arcGIS to create outline around points (isochrone) [duplicate]

I am trying to generate my own iso-chrones using Google and Python and have reached a point where I can produce two data-sets which I would like to combine in the following way: Points (reachable ...
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9answers
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Maximizing the use of CPU

My script is intersecting lines with polygons. It's a long process since there are more than 3000 lines and more than 500000 polygons. I executed from PyScripter: # Import import arcpy import time # ...
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4answers
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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 ...
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3answers
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Using variables from one Python script in other Python scripts?

I want to set up a single python file containing variables that have the locations of all my data sources. This would then be used by all my other scripts, then as a data source changes, I only have ...
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4answers
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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 ...
8
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4answers
319 views

Subset Folder Contents ArcPy

I have about 1500 .txt files within a folder named 3410001ne => 3809962sw. I need to subset about 470 of these files to process with a Python script. Below is the section of code prior to my for ...
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4answers
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Accessing attribute table within shapefile and replace values?

I would like to find a Python script that will access an attribute table within a shapefile and either update or replace records inside a field column. More specifically, I would like to use the ...
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3answers
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How to convert geoJSON to python objects?

New to the site, and to geoJSON, and to python. My goal is to read in a file with geoJSON data, and use it to generate shapes to be used in an application that is using python scripting. Python has ...
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2answers
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How does one access a featurelayer in SDE via Python?

I am trying to use Arcpy to run the CopyFeatures_management script so that I can copy a featurelayer in SDE. What do I use for the input (and output, for that matter, since I'll be copying the layer ...
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2answers
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What are pros and cons of Python add-ins vs .NET add-ins to ArcGIS for Desktop?

I found in ESRI .NET help: Python All ArcGIS Desktop applications include an embedded scripting language called Python. Many areas of ArcGIS—particularly geoprocessing—are accessible through ...
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1answer
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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?
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4answers
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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 ...
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5answers
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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 ...
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5answers
868 views

python.multiprocessing and “FATAL ERROR (INFADI) MISSING DIRECTORY”

While trying to do multiprocessing with arcpy, I am occasionally running into this error: FATAL ERROR (INFADI) MISSING DIRECTORY I have no clue what is triggering this error, and it crashes the ...
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6answers
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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 ...
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3answers
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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 ...
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4answers
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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 ...
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3answers
314 views

Performing a Spatial Query in a loop in PyQGIS

What I am trying to do: loop through a point shapefile and select each point that falls into a polygon. The following code is inspired by a spatial query example I found in a book: mitte_path = ...
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3answers
3k views

GDAL and Python: How to get coordinates for all cells having a specific value?

I've got an Arc/Info Binary Grid---specifically, an ArcGIS flow accumulation raster---and I'd like to identify all cells having a specific value (or in a range of values). Ultimately, I'd like a ...
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2answers
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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 ...
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6answers
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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 ...
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1answer
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Difference between Make Feature Layer (Data Management) and using in_memory workspace?

I was wondering the difference is between Make Feature Layer (Data Management) and using an in_memory workspace? To me, one can use either to do some steps in memory, instead of writing data to a ...
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Convert timeseries stack of GTiff raster to single NetCDF

Moving from gdal-dev mailing list: On Mon, Sep 2, 2013 at 7:09 PM, David Shean wrote: Hi list, I'm trying to package a timeseries of GTiff rasters with identical projection/extent/resolution as a ...
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1answer
872 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). ...
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3answers
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How to use QGIS Zonal Stats Plugin from Python Console?

I am using the Zonal Stats plugin in QGIS to extract raster statistics from overlaying polygons (I have shapefiles of species distribution and I want to extract environmental data from within each ...
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3answers
513 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 ...
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4answers
511 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 ...
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4answers
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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 ...
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1answer
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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
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1answer
458 views

Why the order of imports matters in a standalone PyQGIS processing script?

I've come across a weird issue while running standalone PyQGIS processing scripts. The order of imports in the script affects its normal execution. You can reproduce the problem by opening a Python ...
8
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2answers
711 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 ...
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2answers
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Using the python shape library: pyshp - how to convert .csv file to .shp

I am trying to understand how I can use the csv module in python to open a csv file in the same folder as the python script, and then create a shapefile using the shapefile module pyshp. The csv file ...
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6answers
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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 ...
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2answers
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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 ...
8
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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 = ...
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2answers
1k views

Calculate Date Field - today's date from datetime.date.today

I'm working on part of tool that will use arcpy.CalculateField_management to add the current date to the attribut table. I've wandered far and wide on the interwebs and can't seem to find the ...
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1answer
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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, ...
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315 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 ...
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1answer
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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
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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 ...