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

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399 views

How to use `layer.getFeatures()` in a standalone script?

I am following the QGIS Cookbook and this post where it concerns reading attributes from layers. I would like to exploit this method and implement it into a standalone script. Essentially, I want to ...
2
votes
1answer
2k views

Install gdal in python on Windows7

I'm having problems installing the gdal library for python. I use a Windows 7 and have WinPython 2.7.9.2 which runs Python 2.7.9. I'd like to use gdal + Python for raster manipulation. I've read ...
2
votes
2answers
293 views

What is the “best” way to automate the GIS slope and aspect algorithm?

I am currently obtaining slope and aspect of roofs using ArcGIS as follows: Mosaic several Lidar .asc files to new raster Extract by mask using Mastermap building outlines to get hold of just the ...
2
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1answer
267 views

Python tool won't stop running— Not an infinite loop issue

I'm having trouble with a python script. It is essentially a near duplicate of another script which is running fine-- it is using different files, but apart from that the tools used and the order in ...
2
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2answers
205 views

Script to convert line segments to equally spaced points based the duration between points as specified in another field

I have a single file containing several hundred line segments created through connecting points collected detailing animal movement patterns. Each segment has a "seconds" field and a "uniqueID" field....
2
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2answers
415 views

Batch add column to layers and add layer prefix in PyQGIS

I have a number of layers each with a prefix like A_ B_ and so forth. I'd like to: Add a column (text) called DENSITY to each shp Add the prefix letter from the layer name to each row in the ...
2
votes
1answer
929 views

Using ArcPy to Read from Excel Spreadsheet to Python Dictionary

How would I go about creating a script that reads a specified excel spreadsheet and places the values in a dictionary? I have read about the xlrd library and how the library in such endeavors to read ...
2
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3answers
95 views

QGIS python plugin appends values every time it's started

I've written a small python plugin (using plugin builder as base) to simplify the expression process for a given layer (just a few comboboxes that are used to create a query). The combo box populating ...
2
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1answer
783 views

How to add label to QgsVectorLayer by Python

my goal is to define label programmaticly for the case similar for the figure below: But didn't find any guidance how to do so using Python. I have a feeling it could be done using QgsLabel but ...
2
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1answer
479 views

Getting a number from QLineEdit and passing it to the buffer function

I am developing a plugin which finds buffer. In that i am using lineedit for getting distance from the user and pass it to the buffer function. My current code throws an error "'QLineEdit' object has ...
2
votes
1answer
563 views

How to move layers in the QGIS Table of Contents via PyQGIS?

I have loaded two layers in canvas and would like to move the layers using the following code in TOC, but it is not moving the layers to the position based on the index given. from PyQt4.QtCore ...
2
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1answer
583 views

How to apply a filter to multiple vector layers in QGIS?

I am trying to apply an attribute filter to multiple layers in QGIS at once. The filter is to be applied to .osm data brought in through PostGIS to QGIS. I have tried selecting multiple layers -> ...
2
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3answers
453 views

Why script works on my computer but not on another?

The script below works perfectly fine in my computer. But when running the script on another computer, I receive an error: Error: Algorithm not found The computer has similar specifications to ...
2
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1answer
2k views

Where should PythonWin be located?

I have a question about PythonWin. Does it come with the DVD when you install it or does it have to be installed manually separately from the ESRI DVD ? On my computer at work, it does not come with ...
2
votes
1answer
228 views

How to read X,Y from mouse click in Python

I am looking for some advice… I am trying to build a tool that will precisely (10digit, eg: AA1234512345) identify British National Grid (BNG) by clicking on a map. The ArcGis default tool can only ...
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2answers
471 views

Select Layer By Attribute to be used in for loop

I'm trying to iterate through a feature class and select each feature one by one by using the OBJECTID field. When I use a single value, the SelectLayerByAttribute works, but how do I compare the ...
2
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1answer
261 views

Command line error and missing dependency in QGIS

I have two problems with QGIS 2.6.1 1) When i am trying to open command line i get error: An error occurred during the execution of Python code: Traceback (most recent call last): File "C:/OSGEO4~1/...
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3answers
304 views

Using GDAL translate in Pythonwin

I want GDAL translate in Pythonwin to process some GeoPDFs to GeoTiffs. I can't call up GDAL module in Pywin. I used the OSGeo4 installer for original GDAL install and can leverage GDAL properly from ...
2
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1answer
163 views

geting geograpic locations from an address list

I have a table with 150 addresses. I would like to automaticly generate a point shapefile/PostGIS layer from all of them. Is that possible in any way or do I have to search for every single address to ...
2
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2answers
128 views

How to encode a point geometry in Geojson?

I have point geometry in posgresql which I query as follows: select ST_AsText(geom) as pointgeom from pointable. I'm using python as server side script. I want to pass the result as Geojson response ...
2
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3answers
3k views

Converting personal geodatabase .mdb file to .gdb

Is it possible to convert an MS Access personal geodatabase file to a SDE enterprise geodatabase file format? What kind of python scripting would it entail? I need to convert it in such way to ...
2
votes
2answers
222 views

With QGIS Plugins/PluginBuilder, how to prevent 2nd instance of Plugin from starting

I am using QGIS 2.6.0, with PluginBuilder 2.0.3 [checking the version, I just noticed that the 2.1.0 update is available] I am writing a plugin; it installs and runs. While running, I am able to ...
2
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1answer
78 views

Referencing fields in code block of Field Calculator in ArcGIS for Desktop?

I'm trying to use values from a field to fill a new field with a truncated version. The 'str.rindex' function is working out well, but I can't seem to figure out how I'm supposed to reference the ...
2
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2answers
686 views

I've downloaded the GDAL-1.11.1 package but why can't I call on it in python?

I have a Mac and am very new to this coding stuff.. I'm using a code that includes import osgeo as gdal and so I've downloaded GDAL from https://pypi.python.org/pypi/GDAL/ which has a folder ...
2
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2answers
462 views

Store result from gdallocationinfo as variable in python?

I'm trying to find the cell value at various locations in a set of rasters so I can count the number of real values (aka not 'NoData') that occur at all the locations within each raster. The various ...
2
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1answer
150 views

Grass python shell can't find my data

I have a problem, the grass 7 python shell can't find my rasters. When I try to use the python shell to set the region I get "region not found". I can set the region in the grass shell (and other ...
2
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2answers
111 views

Returning value from other field, using FieldCalculator

I am very new to Python and need what I believe is a very basic script in order for my field to represent another fields' input, if the field's value is 0. I tried to search for this, but gave up ...
2
votes
1answer
127 views

Trying to generate a PDF for each feature in a feature class based on an attribute with Python.

I have a feature class of points that represent storm water inlets. I am trying to automate a process that does the following. finds all of the inlets that have a field called "Marker" populated ...
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4answers
422 views

Field Calculator Python Expression Issues

I'm pretty new to Python and this is my first post on this forum so I could use some help. I am currently attempting to run some code in the Field Calculator in a model in order to replace string ...
2
votes
1answer
570 views

ListRasters based on filename using Arcpy

I am trying to create a python script for ArcMap which calculates the ndvi from two raster images for each RGB/NIR pair in a folder. However, I am unsure how to create two raster lists; one which ...
2
votes
1answer
169 views

How to create Multipart Line in ArcPy?

I am developing some script in where I want to create custom multi part line geometry. For example: I have one array of points a,b,c and second array of points e,d,f. I want to create one ...
2
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3answers
3k views

List all Feature datasets & feature classes from a single geodatabase into CSV

I have prepared a python code and I got the following errors: "Parsing error IndentationError: expected an indented block (line 11)" and "Runtime error Traceback (most recent call last): ...
2
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1answer
498 views

Migrating data from Python to PostGIS

I have pandas DataFrame with these columns: point datetime value 1 Point(-24.6064453125 26.3683280945) 2014-09-11 19:00:00 24.885258 2 Point(-...
2
votes
1answer
405 views

Python Use SearchCursor/InsertCursor to split attributes in fields

I download data daily and create a geodatabase table. Fields: Company, Customers_Active, Customers Total, County, State Example Data {CompanyA,CompanyB}, {141,424}, {1000,3421}, Cook County, ...
2
votes
1answer
815 views

Installing Pandas in ArcGIS 10.2 for Desktop?

I followed the very clear directions in the answer to Installing pandas with Esri's python? and created the Esri101 build and added a "conda.pth" file to my C:\Python27\ArcGIS10.2\Lib\site-...
2
votes
1answer
397 views

Unicode Decode Error for shapefile in Python

I have Python script for converting shapefiles to Geojson. My code works well if I use some usa data, but when I want to use some other encoding, it gives me this error: Traceback (most recent ...
2
votes
1answer
269 views

Open a .osm.pbf file with fiona in python

I would like to open a .osm.pbf using fiona in Python. I can't find much documentation on this. How can I does one do this? I have done it using ogr2ogr.
2
votes
1answer
108 views

Get min-max values of a raster and populate two parameters with the values in tool validation script

I am customizing the script tool behaviour of a custom script and would like to get the min-max values from a raster self.params[0] and populate the next two parameters, self.params[1] and self.params[...
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2answers
79 views

Selection of lines that lays mostly in defined zone (majority overlap)

I have lines of surface runoff and I need to select the ones that are lying mostly in internal buffer of polygon. I'm trying to make some script in python, but it's very important to make the script ...
2
votes
1answer
282 views

Arcgis, Convert analyse result in numeric value

I have a problem that seems really simple but blocking me... in Arcgis i have script python where i want to extract the resolution of a raster and use this result like numeric value for use in a ...
2
votes
1answer
68 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 ...
2
votes
2answers
506 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 ...
2
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2answers
81 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
519 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
votes
1answer
163 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
votes
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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2answers
423 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 ...
2
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2answers
132 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
2k 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
407 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 ...