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

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ImportError: libqgis_core.so.2.9.0: cannot open shared object file: No such file or directory

I installed qgis in debian linux and I want to run a standalone app in python. So I import qgis.core and qgis.gui in this app. But it gives me an error: ImportError: libqgis_core.so.2.9.0: cannot ...
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56 views

gdal ReadAsArray returning NoneType

I'm trying to read in several rasters as array using gdal in a python script, but I keep getting NoneType returned and can't figure out why. The process is this: 1. Use gdalbuildvrt ...
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2answers
60 views

How to get cell value along Flow Direction

I have: a flow direction raster where I took off (assigned NoData value) the cells that overlayed the river network (from flow accumulation). a perfectly overlapping raster where I asigned a ...
0
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1answer
59 views

Is it possible to embed python in code for HTML pop-ups in ArcGIS

When clicking a point feature I want the html pop-up to not only contain the data of the feature but also an image of the area around the feature (eg. 2 km^2). The image would have the base map 'World ...
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2answers
153 views

Why is my cursor empty?

Yesterday I set up a Python script using a cursor on a layer. Today I've tried running again and no matter what I run it in, the cursor is empty. I've tried removing the query on the layer, tried ...
2
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1answer
43 views

Python FindLabel Function for Label Expression with Formatting Font?

I originally had this FindLabel function (which works)... def FindLabel ( [NAME], [Count_] ): if [Count_] != None: return [NAME] +'\n' + "Well Log Count: " + [Count_] I wanted to format the ...
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1answer
43 views

Cannot rename output file using standalone script for QGIS

I would like to rename all output files after my script has finished processing them by adding "(A)" after their file name (eg. Layer.shp -> Layer (A).shp). I received an answer from this post on the ...
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1answer
68 views

Problem exporting ecw project- arcpy

I work with arcview 10.3. Every time i export maps with ecw raster format , python (version 2.7.8) get crashed and i see: I use this code: import arcpy,os,sys,string import arcpy.mapping from arcpy ...
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1answer
58 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 ...
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3answers
60 views

SearchCursor Index Out of Range

I'm using ArcGIS 10.2 and trying to obtain values in a field using SearchCursor. Would someone help me with this? import arcpy oc = r"C:\Users\Scratch\oc.shp" catchments = ...
2
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5answers
167 views

How to export attribute table with start and end coordinates of lines to Excel?

I am working in QGIS. I have a georeferenced line layer and I want to export the attribute table and the coordinates of start and end points of my lines to Excel. Can I do this with QGIS?
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56 views

How to add multiple attributes to a newly created feature with PyQGIS

I am creating a form for updating the attribute values of the newly created feature. But when i am updating the values only one attribute field is getting updated. So if i want to update the multiple ...
2
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1answer
60 views

Does mapCanvas().refresh() not work in QGIS 2.6?

Before I used the function qgis.utils.iface.mapCanvas().refresh() to reload the map canvas after for example a layer color was changed from a plugin. But this is not working with QGIS 2.6 for me. ...
2
votes
1answer
119 views

ArcGIS Python syntax error using nested if else

I am trying to use the field calculator in ArcMap 10.2 to fill an empty field based on the contents of two exiting fields usint this python script in the Pre-Logic Script Code. def ...
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0answers
19 views

Raster Vector stack

I want clipped image of NDVI for a particular area. I did raster calculation for getting the image with NDVI values. After that I tried extraction function clipper. In this function we have to use two ...
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1answer
68 views

How to export only certain column from selected feature to csv file in QGIS using python code

I have selected features in QGIS, I want to export only two columns from the selected features to a csv file automatically using python code. I have tried the following code: layer = ...
3
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2answers
62 views

How to define layer's CRS and avoid the CRS dialog in PyQGIS?

There is an existing Shapefile, which I want to add. At the moment my code looks like: self.iface.addVectorLayer(self.shpFilePath, "Track", "ogr") It works fine, but i want to define the crs ...
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1answer
58 views

Download file from network using PyQGIS 2.x

I have a python plugin targeting QGIS 1.8 that uses QgsNetworkAccessManager and QNetworkRequest to issue a GetCapabilities request to WMS servers. With 1.8 everything was working fine. Now we are ...
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61 views

Polygon of Voronoi cell using scipy.spatial?

I have points (e.g., lat, lon pairs of cell tower locations) and I need to get the polygon of the Voronoi cells they form. from scipy.spatial import Voronoi tower = [[ 24.686 , 46.7081], [ ...
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1answer
66 views

Unable to merge two shapefiles (created from text files) using ArcPy? [closed]

I am trying to merge 2 shapefiles together created from 2 text files. I am new to python and managed to get the textfiles into shapefiles, however, when trying to merge the two newly created ...
1
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1answer
51 views

Problem with tool validation script in ArcGIS?

I have tried to write some validation code for a script in ArcGIS. This validation code more or less repeats what the script itself does, which is a simple cutting up of a long string by using the ...
2
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0answers
25 views

QGIS Python Script for RoadGraph plugin

I am looking to create a Python script that will take X,Y coordinates from one field in an attribute table, compare them to another set of X,Y coordinates in a different field, and populate a field ...
2
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1answer
47 views

Issues with PyQGIS while running a QgsZonalStatistics script

I have experienced a very bizarre issue with my PyQgis code. I simply want to load a raster and a vector layer to do zonal statistics, the first part works perfectly but for the zonal statistic I have ...
3
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2answers
134 views

How do I serve OSM map tiles (mbtiles) from a Raspberry PI 2?

My main processing machine is a Ubuntu box running 14.04 with PostGIS and TileMill. I generated my tiles and the resulting mbtiles export is about 250MB (megs, not gigs). The PI runs python, has a ...
2
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1answer
63 views

Difference between osgeo gdal/ogr python module and GDAL C++ library

I am developing application in python and I use the osgeo gdal/ogr python bindings for gdal, but its not clear to me what exactly is the difference between the gdal/ogr in python and the gdal library ...
6
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1answer
286 views

How to compute Straight Skeletons using Python?

Is there a Python package which provides an implementation of a Straight Skeleton algorithm? I'm aware that the open source (C++) project CGALcontains an implementation but it seems like ...
0
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1answer
35 views

How to connect mouseclick to map canvas in QGIS?

How to connect mouse click to map canvas in QGIS using python script? I have two lines of code to connect mouse click to map canvas: button.clicked.connect(self.onClicked) ...
2
votes
1answer
55 views

Error with Python Script using Shapely

My professor gave us a basic Python script that demonstrated how Shapely works with a shapefile, however it's not working for me. Here is the code: from shapely.geometry import mapping, shape from ...
0
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1answer
59 views

How to trigger a QGIS action when a plugin button is clicked?

I tried calling the select free hand tool by below snippet of code. iface.actionSelectFreehand().trigger() I dnt have any idea how to call this when i am pressing a button in GUI. my gui is ...
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1answer
66 views

How to call default tool in QGIS inside plugin using python script?

I want to create a plugin which can draw irregular polygons in QGIS. For that, I want to call the Select features by freehand default tool inside my plugin. How can I do this within a python script?
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39 views

web2py - openlayers

I have used web2py and there is test.py under controllers which shows a map as below: and its code is: for url in [ 'http://dev.openlayers.org/theme/default/style.css', ...
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2answers
97 views

How to add XY point and update attributes with ArcPy 10.0

I would like to create a script tool that takes 3 parameters in ArcMap: Google maps coordinate (e.g. -33.876846, 151.215117) text string text string The coordinates would define the XY geometry, ...
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1answer
63 views

QGIS (2.6.1) Processing Toolbox InitGui error after changing /Users folder on Mac OSX

Using: Mac OSX 10.9.4 QGIS 2.6.1 I had previously installed QGIS and had everything running fine. My home directory was /Users/rowanbado, but for another application I had to add an ...
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2answers
153 views

ArcPad Checkout from python command line

I have been developing a script to automate my ArcPad checkin/checkout processes. My problem is that I am having trouble getting arcpy to recognize the ArcPad tools from the command line. From the ...
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3answers
61 views

How to return a unique value from table using Arcpy?

Using Arcpy in Python, I would like to return / print '0.15' from the following table: When I use the following code I get "(u'D', 0.20)" as my print statement in Python: import arcpy fc = ...
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2answers
73 views

Shapefile projection for Matplotlib Basemap

Preface: First time working with GIS data. I'm using python's Basemap library for overlaying data on maps. The tutorial I'm using includes a shapefile for London (london_wards.shp). I use the ...
1
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1answer
25 views

Creating ArcGIS tool that can run list of checks?

Is it possible to create a tool in Arcmap where by uploading a shapfile, the tool can run a various number of checks/tests (ie intersecting other shapefiles) and flags or highlights conflicting ...
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0answers
32 views

QGIS 2.6 SAGA Processing Algorithm, “Add grid values to shapes”, produces NULL Values

I'm using QGIS 2.6 Brighton on Windows with SAGA 2.0.8 installed using OSGeo4W. I have the same versions installed on OSX as well which is not having this problem. On Windows, I'm trying to extract ...
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2answers
141 views

Debugging 'module' object has no attribute 'SdeWorkspaceFactory'?

I am new to python, am debugging one of existing python code, where am facing an error "'module' object has no attribute 'SdeWorkspaceFactory". Earlier this code was working fine but suddenly does not ...
0
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1answer
63 views

SyntaxError: can't assign to function call, arcpy set parameter as text

I have a python script loaded into arcgis ModelBuilder, and when I run the model I keep getting an error when the script tries to run, at the line where I am setting the output as a text parameter. ...
2
votes
1answer
52 views

QGIS gets stuck when running script to automatically refresh layer [closed]

I have a QGIS layer that represents a set of links and nodes to show the streets of a city and the traffic speeds on each street. I've been trying to write a script so that if I change the speeds in ...
1
vote
1answer
52 views

How to exclude a certain attribute from being added to the Processing script output layer?

I have a working script to split a layer by field attributes and save the single features as files: ##[User scripts]=group ##input=vector ##class_field=field input ##output=output file from ...
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2answers
147 views

Using Python in the field calculator - if/else over multiple fields

I'm trying to work out how to populate a field depending on the lowest score across 6 other fields. I've read several other questions relating to if/else statements but I'm only just starting to learn ...
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0answers
48 views

How to set time field when generating a GPX track with Python OGR?

I want to generate a GPX file with Python OGR. In particular I want to generate a tracks (layer of features of OGR type wkbMultiLineString) My script is below. I get the error ERROR 1: No such field: ...
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0answers
42 views

Is there any way to create user login for single project in QGIS?

Is there any way to create user login for single project in QGIS? I want to track changes on database when users update features. I know that I can do this on database level but is there way to do ...
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28 views

Invoke PostGIS geocode function using Python

I have a PostGIS Geocoder built with using Tiger data. Using SQL, I am able to execute all database functions and queries. I want to use it with my Python program. One of the option would be to write ...
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0answers
30 views

How do I compute uncertainties in the positions transformed using Helmert transformation?

I am familiar with Python, MATLAB and Mathematica. My data is given by Cartesian coordinates (positions in X,Y,Z (meters), standard deviations XX, YY, ZZ (meters) and a correlation matrix (XY, YZ, ...
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2answers
41 views

Performing batch Join Field in ModelBuilder?

I have a list of 250 feature classes (X1, X2 X3, ...) which all have an individual field that I want to join to another feature class Y. The join can be established through a common field that are ...
3
votes
1answer
48 views

What is the replacement for 'setColorShadingAlgorithm' in QGIS 2.6?

I have been struggling with setting the colorshadingalgorithm for a raster layer in QGIS with no success for the past few days. The QGIS cookbook seems to be pretty outdated. Anyways, the code that I ...
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1answer
38 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 ...