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

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1answer
67 views

What are resources to learn ArcGIS for someone who already knew Python [closed]

I know that there are several resources recommendation questions, however, they are all from GIS people trying to learn Python (for example, here). My situation is the opposite: I have worked ...
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2answers
419 views

Writing shapefile with projection defined crashes fiona

I've just started trying to use Fiona to write out shapefiles. I found the example code below, which seems to work fine from shapely.geometry import mapping, Polygon import fiona # Here's an example ...
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2answers
75 views

GetCount raises exception

I opted to use gp.GetCount in my script. This raises an exception, though the process completes "successfully" while returning zero features (which is untrue). I'm wondering how this could be. Using ...
2
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1answer
340 views

Error: Algorithm not found

I wrote the following code to start using QGIS APIs. in a very short script seen below, the "Error: Algorithm not found" is thrown and "print processing.alglist()" is showing none. Any idea why this ...
2
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1answer
139 views

How to open most recent directory using PyQGIS?

For example, when I add a vector layer, next time that I want to add another layer it opens up where I chose my last layer from. How would one implement this in Python and/or PyQgis? I'm writing a ...
2
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1answer
1k views

How to compare string fields in the same table with ArcGIS 10

I don't know exactly if there is a tool for this or a maybe a python script could be more suitable. I want to compare string elements from a field (POI_NAME) with another string element in another ...
2
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1answer
1k views

How to open a shapefile using Python in QGIS?

I have tried to open my shape files with the help of a tutorial (http://spatialgalaxy.net/2012/01/27/qgis-running-scripts-in-the-python-console/) but unfortunately I couldn't open my shapefiles for my ...
2
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2answers
308 views

PyQGIS: How to send signal if layer is currently in edit mode

I'm looking for a way to send a signal if a layer is in editing mode. I tried editingStarted(), but it wasn't working. I'd like to do something along the lines of the what I have below, but can't find ...
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2answers
124 views

ArcGIS - Extract by Attibutes in Model Builder

I have a model which at one point uses the Extract by Attributes tool to produce a new raster with just the areas containing the maximum values of the first. I would think that the SQL expression ...
2
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1answer
1k views

gdal polygonize in python error, blank polygon created

I am having trouble using the Polygonize function in python. The cookbook example for this can be found here. The relevant portion of my code is: sourceRaster = gdal.Open('myraster.tif') band = ...
2
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1answer
357 views

PyScripter crashes at “import processing”

I set up PyScripter latest version, 2.7) to work with QGIS (2.2, OSGeo4W install) following http://chelahmy.blogspot.ca/2011/02/setting-up-pyscripter-for-quantum-gis.html. It generally works well. I'm ...
2
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1answer
380 views

Mac OS X 10.6.8 QGIS not using user-installed Python 2.7

My QGIS does not recognize the recently installed python 2.7 on my mac osx 10.6.8. it still uses the python version 2.6 that is automatically installed by apple. Opening qgis I always receive an ...
2
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2answers
296 views

raster standard deviation stretch python script

I am looking for ways of applying a permanent standard deviation stretch to rasters via python script. Are there any arcpy raster stretch functions? I was looking for a reference but could not find ...
2
votes
1answer
927 views

Importing otb into Python

I have Python 2.7 (installed together with ArcGIS 10.1). Via OSGeo4W a have installed qGIS and otb application.I was able to connect qGIS and otb and it's working fine. Through OSGeo installer I ...
2
votes
1answer
125 views

How to Export multiple selected features to PDFs with Python?

I have 77 polygons that mark areas of a satellite image that I want to export as separate PDFs. Each of the PDFs should contain just the polygon (and as much as the surroundings to fill out the data ...
2
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1answer
466 views

Why does OGR driver.Open() for File Geodatabase give AttributeError: NoneType object has no attribute Open?

There are a number of existing Questions that hint at a possible Answer to this Question, but none seem to be providing me with the solution to my problem: How to access feature classes in file ...
2
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2answers
439 views

Python Def Query Help for multiple layers

I have Three layers in a .mxd, all three layers have a common value I can use, but a different Label in each Layer. As an example, the Value I want to use is "100" In Layer A, the Value is in [Name] ...
2
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1answer
134 views

Populate an attribute table field using the 'startswith function

I am hoping that someone may be able to help me. I am new to ArcGIS, and even newer to Python. Working in ArcGIS 10.1, I have done is created a new text field in an attribute table, which I have ...
2
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1answer
583 views

GDAL polygonize only certain raster values

I want to polygonize a raster file with GDAL. I only want to rasterize cells with a value of 0. Is it possible to specify that within the polygonize function or do I have to modify my raster before ...
2
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1answer
986 views

How to label vector features programmatically?

I am using python for QGIS 2.0.1 and I have a vector layer of points representing the positions of state labels. I want to display the 'state abbreviation' attribute on the corresponding point for ...
2
votes
1answer
141 views

Why is arcpy.mapping.ExportToPDF losing layer symbology?

When exporting a map it does not export the symbology within the data frame. I am using the code snippet below. >>> myMap = arcpy.mapping.MapDocument("C:/USERS/NISUSER/DESKTOP/mxd_map.mxd") ...
2
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1answer
80 views

How to run shapefile.py

I'm script challenged and trying to repair a shapefile with a missing .shx. This tool sounds ideal: https://code.google.com/p/pyshp/, but the four step instructions are not enough. Can someone give me ...
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2answers
487 views

Get Index for a group QGIS Python

I am trying to add new layers into a specific group which I can get to work if I know the index but how can I get python to fid the index of a group so it can load the new layer into the group ...
2
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1answer
1k views

How to install QGIS 2.0 on Mint 15?

Trying to use QGIS 2.0 on Mint 15 (based on Ubuntu 13) I installed, uninstalled and re-installed QGIS from various repositories (ubuntugis-unstable, then qgis.org/debian raring - not clear for me ...
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3answers
3k views

Python script for identifying duplicate records (follow up)

I am trying to calculate a field that marks duplicates and sequentially numbers them. I am using the code below that I found here: Generating sequential numbering for duplicate values in a field ...
2
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1answer
334 views

OGR: How to best use GetFeature on a selection?

I think the following is very confusing sel_str = "ND_14 = '108'" l.SetAttributeFilter(sel_str) l.GetFeatureCount() >>> 1 In a for-loop this gives me for f in l: g = ...
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2answers
403 views

Erase method using ogr

I'm trying to find the erase geoprocessing method as i am familiar with in ARC, but i can't seem to find it in OGR using Python. I have looked through the module ogr documentation but perhaps i missed ...
2
votes
1answer
410 views

Programmitcally Change Text Font for all Labels on MXD

I'd like to know if there is a way to change the text font for all layers and all label classes within a layer on a MXD. I use a font not often found on all computers for created maps. I love the ...
2
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2answers
255 views

Determine ArcCatalog's currrently selected folder using Python

Is there a way to get the current directory opened in ArcCatalog 10.0 using Python? Something like os.getcwd() but instead gives the selected folder on the catalog tree. Cheers
2
votes
1answer
1k views

Tool to convert Mike Urban network (shapefiles) to EPAnet network

This might be a too localized question, but I hope I'm not the only one here doing pipe network analyses in Mike Urban. I have a model in Mike Urban, and the client wants it in EPAnet format (since ...
2
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2answers
612 views

How can I perform an inside clip on a raster file based on another raster file?

I have a raster file that I would like to use to perform an inside clip on another raster file. I have tried using the extract by rectangle tool, but it gives me values ranging from 3.40282e+038 to ...
2
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1answer
390 views

Need a Python field calculation that works like the DatePart( ) VB Function

I have a field called Abandoned Year (short integer data type) that I am trying to populate with a four digit year from a column called Decommission Date (Date data type). I have done this in the ...
2
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2answers
74 views

How to travers fields of records without introducing them all in the function?

In my previous question I wanted to reach a field in the field calculation; however, it was pretty easy to introduce a few more inputs for that function. Now, I am facing a problem which needs around ...
2
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1answer
288 views

How to store attributes of a large shapefile in a list?

I am trying to store the attributes of a shapefile into a list. With following code it works for smaller shapes: addA = [] While provider.nextFeature(feat): attrs = feat.attributeMap() for ...
2
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1answer
530 views

Generate unique ID upon creating a feature?

Looking for a way to generate a unique Global ID within a feature set when a new feature is created. For example, every time a sewer manhole is added, we need to generate a new unique Global ID that ...
2
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1answer
1k views

How to get point x and y geometry from a shapefile?

I have a shapefile of US Cities and I want to get the X and Y coordinate of EACH city in that shapefile. I've tried this: for city in city_cursor: geom = city.Shape point = geom.getPart() ...
2
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2answers
2k views

How to calculate volume from a raster file?

I have a raster file containing the depth of water. I need to find the volume of water using that raster file. I need to find the area of each cell and multiply with the depth. How can I do it in ...
2
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2answers
2k views

How to Add Shapefile with Symbology from Layer File to ArcMap MXD using ArcPy/Python?

Say I have a Shapefile: C:\DATA\points.shp A layer file: C:\SYMBOLOGY\symbology.lyr And a map document: C:\MAPS\map.mxd How can I add points.shp to map.mxd with the properties of symbology.lyr ...
2
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2answers
345 views

How can I set the settings of an Address Locator within a Model or arcpy?

I am creating a model that processes a large road dataset, then creates an address locator from the roads. The Create Address Locator tool does not allow me to set options like Spelling Sensitivity or ...
2
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3answers
529 views

How to test if geometry is inside another?

I need to tell whether geometries from a shapefile are inside other geometries or not. For example, I want to test if there are trees (represented as points in trees.shp) inside the urban areas ...
2
votes
1answer
723 views

How to “Merge Selected Features” with python?

I have been looking for the answer to this question for some time now, but can't seem to find it! My problem is straight forward: I have one layer It contains lots of features (only polygons), say ...
2
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2answers
695 views

upload table to ArcGIS Server

We are building a process which will allow users to submit a table of GPS data to update our central repository for all GPS data. Let's say that the target is simply a SQL data table. At first I ...
2
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1answer
669 views

Error 999998 in Arcpy 10.1

I found an RuntimeError: ERROR 999998: Unexpected Error when lunching Arcpy in my ArcGis 10.1 such as this: Runtime error Traceback (most recent call last): File "", line 50, in File ...
2
votes
1answer
492 views

Compare two Digital Elevation Model (DEM)

I would like to know what's the best method(s) to compare two DEMs without using any GUI soft like QGIS or ArcGIS. I'd like to do it in Python or C++, with GDAL or other similar lib. Does calculating ...
2
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2answers
1k views

get value from attribute table and change symbology with QGIS and Python

I'm newbie developing plugins for QGIS using Python, this is the first one and it is very frustrating hehe. Ok, this is the situation, I have a 1 point layer in QGIS. Its attribute table has 4 fields ...
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2answers
1k views

Where exactly are qgis.gui and qgis.core located?

I'm trying to create a standalone qgis app using pyqgis, i'll be deploying it by copying the install folder of qgis and source folder of my app, and so for the testing purposes i copied qgis install ...
2
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1answer
1k views

Python - read shapefile .dbf for encoding

I've written a python script that formats a .shp such that its fields structure matches my office's database view in order to ingest the data of said shapefile. This original shapefile was encoded ...
2
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1answer
2k views

QGIS Python version

I have brewed python 2.7.3 onto my Mac (Lion), and installed shapely via pip install shapely. The Polygonizer plugin, however, does not find the shapely library. I see when QGIS loads a Python ...
2
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1answer
642 views

How to use ArcPy cursor to define each feature sequentially as current selection of layer?

I want to implement a script that runs through each feature of a feature class, zooms to the extent of the feature, sets the scale to 1:5.000 and adjacent takes a picture of the scene. The steps are ...
2
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1answer
575 views

Setting parameters in Arcmap for dynamic python script

I have a simple python script that works when run from PythonWin, but when I try to make it dynamic to run inside ArcMap I keep receiving: : ERROR 999999: Error executing function. Failed to execute ...