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

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Is it possible to rotate the geographic projection in QGIS?

I'm trying to create a Qgis plugin that can rotate a raster layer in the canvas so that the north is pointing at another direction. Unlike the thread below, I'm open to defining a custom projection. ...
-2
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0answers
33 views

Update fields in feature class [duplicate]

I am working on ArcGIS 10.2.1. I have a feature class containing more than 4000 records and a table having approximately 1000 records. Both feature class and table have some common fields however, ...
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1answer
57 views

What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?

What is the inverse operation of QgsGeometry.asGeometryCollection() as documented here: http://qgis.org/api/classQgsGeometry.html#a7cb1cbf8cfa441456067a66ad3a25a94 I'd like to do something like: ...
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1answer
67 views

Updating a feature class

I am working on ArcGIS 10.2.1. I have a feature class containing more than 4000 records and a table having approximately 1000 records. Both feature class and table have some common fields however, ...
2
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0answers
19 views

How to snap dangling nodes with prescribed angle?

I have got a streets shape file, to snap the dangling nodes in ARCGIS. But, I have to snap only some nodes(of feature) with a prescribed angle (green node in the image, and the angle marked in ...
2
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1answer
24 views

raster overlap count

Would it be possible to simply detect and count overlaps between raster files, i.e. not polygons against rasters, using arcpy? By default I don't have the spatial analyst extension for ArcMap 10.1 but ...
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35 views

ArcGIS 10.2 with MatPlotLib Non-Blocking Plot

ArcGIS 10.2 ships with MatPlotLib 1.1.1 installed. I am trying to display a non-blocking plot window. Trials: Launch an interactive plot in a Tk window from a toolbox. This causes the plot to ...
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27 views

Placing Pins and following transformation on zoom map d3

So I am using this http:// bl.ocks. org/mbostock/4699541 framework on D3.js and I just figured out how to append circles to the map. However when you click on a state the circle moves out of place ...
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1answer
25 views

Adding a Vertex To Exisiting Feature(linear) Using OGR Python

I am working on a project that involves finding the intersection of linears in a shapefile, if that vertex(the found intersection) doesn't already exist for each(or one) of the features, then that ...
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2answers
61 views

gdal2Tiles output differs from MapTiler

I'm in need to process a large batch of Landsat images with MapTiler and since the version I'm using (1.0 Beta 2) does not support multiple input files, I created a simple python script that calls ...
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2answers
59 views

Raster' object is not iterable

I'm trying to calculate the percentage of cell counts in new raster and the new raster is created from an old raster based on the Value > 14. In my code, 1st for loop is for original raster and ...
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0answers
37 views

How to go about creating a custom tool/adding special functionality for a web app

In my soon to be developed web app, I will have an image service and also a feature service that is essentially an index to the image service, with all kinds of attributes. I would like for the user ...
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4answers
431 views

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 ...
2
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0answers
24 views

Polygon parcel division in python

Is there an open source tool or module in python that does parcel division of polygons like in ArcEditor?
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0answers
38 views

PyQGIS: Editable Combobox for Value Map widget isses

I am having issues with an editable combo box in QGIS 2.4. The edit widget is set to Value Map with an uploaded CSV. However, if a new values (not included in the key value pair list) is added, the ...
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1answer
108 views

How does one modify selected geometry with a function in qgis python console?

My example use-case is that I want to redistribute vertices along lines as in: Redistribute linestring vertices to specified distance How to create points in a specified distance along the line in ...
2
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1answer
45 views

How to do loops on raster cells with python console in QGIS?

I'm new here and beginner with python. I'm looking for a solution to my problem for some hours but now you are my last chance... I'm using the python (2.7.5) console in QGIS (2.4.0). Is there a ...
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1answer
61 views

Import arcpy using PyScripter or IDLE gives No module named RuntimeError?

I'm trying to figure out this problem. Yesterday I installed PyScripter and since then, scripts doesn't work. When I run any script (in PyScripter or IDLE) which uses "import arcpy", I get this error ...
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1answer
92 views

How to write output from subprocess to disk (using multiprocessing)

This code was developed from another question I posted about how to kill an arcpy tool if it takes longer than a specified time. See How to cancel tool execution in python. Using the multiprocssing ...
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1answer
60 views

What is the syntax for Python 2.7 to permanent display in percent in a field column?

What is the syntax to build to calculate field, for example, Acres to Percent? 841173.00 to 82 % What I want the field column in Percent to be display numbers with percent with the alignment to ...
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2answers
62 views

Error while importing CSV File using PyQGIS

Currently I am trying to import a CSV file using the python extension in QGIS and I have run into a problem that I can not seem to solve. I am trying to do a basic import of a CSV file from a python ...
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0answers
16 views

How to get sql error from postgis when a plugin fail to load vector layer?

I am writing a plugin for qgis that load a sql layer from postgis database. I am disappointed that when the layer fails to load i can't find a way to get the sql error message from database server. ...
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1answer
37 views

40k+ points from Shapefile, clustering them and populating on Google Maps/Webapp

I just started a new Python/Django webapp job related to GIS (and i'm totally new to GIS). Here is my task and what i have found so far, and i am stuck as to finding out what's the best way or the ...
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0answers
27 views

Import QGIS Python modules in Python command line or standalone script

I am running a Windows 7 machine with Python version 2.7.8 (32 bit). I installed QGIS 2.4 (Chugiak) from OSGeo4W and simply want to be able to import the QGIS Python modules (e.g. qgis.core) into ...
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2answers
42 views

How to find the minimum pixel value within a region of interest?

I am working on a Python script for dark object subtraction, a radiometric correction method for remotely sensed data.To accomplish this, I need to find the minimum band pixel value of a waterbody ...
2
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1answer
48 views

Randomly choosing one from multiple fields in Field Calculator of ArcGIS for Desktop?

Using the Field Calculator in ArcGIS for Desktop, I want to randomly choose one field from a list of 10 fields (strings). The Excel equivalent, which is working, is: =INDEX(A2:J2;rnd()*10+1). How ...
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2answers
54 views

Export Raster Data to TIFF, BMP, or PNG File Using Python

I am writing a Python script to export a Raster Dataset to a TIFF, BMP, or PNG file, as I would manually by right-clicking on the layer, choosing Data | Export Data, and then make my choices in the ...
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0answers
29 views

Link to pdf file through mouse clicking

I need help in identifying the feature attributes displaying a pdf file when click in that feature. I see many examples but I don't have success. I try this code: command = "firefox"; imagerelpath = ...
6
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1answer
178 views

How to classify time periods in a new field, using Python?

I have a datetime field (Horario) in my feature class, showing only the time. Although the date doesn't appear, it seem to be stored automatically as 30 Dec 1899, I'm not sure why. I want to use ...
0
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1answer
39 views

Python for loop doesn't work for Spatial ETL Tool

I've created a Spatial ETL tool from ArcGIS 10.1 and would like to run this tool to all 200 featureclasses in a geodatabase. Therefore, I've written a python script to do this automation. (btw, i'm ...
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0answers
39 views

Using python libary simplejson and urllib in PostGIS

I installed PostGreSQL9.3 and want to create a Pl/Python function using simplejson library and urllib. First I use OSGeo4W Shell to test the similar python script, it works. Then in PostgreSQL, it ...
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2answers
56 views

How to check whether an optional FeatureSet parameter was set by the user in a geoprocessing script tool?

I have created a custom geoprocessing script tool which contains an optional FeatureSet parameter. When unpacking the parameters in the script, the FeatureSet is defined as a RecordSet object, even ...
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1answer
32 views

List index out of range error

I've been writing a script that clips large datasets based on a selected feature. It works fine when I run it in a test workspace where only related layers are active and running. However, when I run ...
1
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1answer
38 views

sum of raster counts

I'm trying to get the sum of "counts" in a raster. I have the code below which can successfully read the counts of each row in raster attribute and stores the counts in a list provided below. ...
2
votes
1answer
31 views

Python Error while installing Cartogram

I am quite new to GIS and qGIS especially. I would like to install cfarmers cartogram plugin. From what I understand, this has to be done manually - so I 've followed the instructions from ...
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0answers
27 views

How to write a custom map canvas item by subclassing QObject and QgsMapCanvasItem?

I'm writing a QGIS python plugin where I place some QgsVertexMarkers on the canvas like this: marker = QgsVertexMarker(self.canvas) marker.setCenter(QgsPoint(point[0],point[1])) Now i would like ...
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1answer
47 views

Using OGR Intersection Method Python

I'm currently working to find the intersections between linears in a shapefile. I'm a newbie to the GDAL/OGR library. I've done some googling and came up with what seems to be a useful example(see ...
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0answers
28 views

How to select duplicate polygons? [duplicate]

Although it may seem this has been answered before, there doesn't seem to be a solution. I am trying to simply select duplicate polygons. I don't want to delete them or anything like that. I need ...
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0answers
37 views

how to create a shapefile containing attributes from a list?

I have a list of features and each feature is a dict in that list. following you can see the structure: [ {"FID": 0, "Shape": polyline, "Nodes": [0,1]}, {"FID": 1, "Shape": polyline, "Nodes": ...
7
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2answers
219 views

Conflict between ArcPy and GDAL/OGR?

TL;DR I can't get an installation free version of GDAL/OGR to work from within ArcMap 10.0. I get an ImportError: DLL load failed on _mod = imp.load_module('_gdal', fp, pathname, description). ...
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0answers
25 views

Exporting ArcSDE feature class to shapefile using OGR?

I'd like to export data from ArcSDE for SQL Server to SHP. I've tried first to run this python script in QGIS: http://trac.osgeo.org/gdal/browser/trunk/autotest/ogr/ogr_sde.py But finally I've got ...
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1answer
45 views

Why does this python OGR code for creating a layer and then adding a field not work?

Spot the difference! So this works... fp = "C:\\LiDAR\\MyLayer.shp" layer = "MyLayer" driver = ogr.GetDriverByName("ESRI Shapefile") data_source = driver.CreateDataSource(fp) srs = ...
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0answers
24 views

Python code to determine the position on a map using Geo-Tagging

What is a proper python code, which enables to scan photographs (when captured from a series of snapshots) and match it with a geo-tagged image database. Based on the extent of similarities existing ...
2
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3answers
122 views

Iterating using search cursor and layer selection performance?

I'm trying to use the results of a search cursor to iteratively make selections on a feature class and then create new feature classes (so you get a new feature class or shp for each unique value in a ...
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0answers
28 views

ArcPy select and merge dropping records from table?

I'm working on a python script for ArcGIS using the arcpy module. I have ArcGIS 10.1 and Python 2.7 on Windows 7 machine and using Notepad ++ and IDLE to run it. The script selects specific records ...
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19 views

CreateObject cannot open map document error when cycling through list of MXDs

I have a stand alone Python script that aims to make a list of data sources from a series of folders/sub-folders full of MXDs. However I am continually getting the: CreateObject cannot open map ...
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0answers
22 views

Gdal_Calc.py random pixel error

I'm using the gdal_calc.py in python in order to do the same thing as the Con tool in ArcGIS. I'm calling the .py using os.system: os.system('gdal_calc.py -A%s -B%s --outfile=%s ...
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1answer
76 views

Summing column values in table using arcgisscripting?

I need to create a python script that sums a column's values in a table. Thereafter, the script is supposed to get the percentage of each individual row in that column and populate this percentage ...
2
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1answer
18 views

OGR DeleteDataSource not working properly in Python

I have a small Python script which is supposed to delete a shapefile in case the file is empty. import sys from osgeo import ogr drv = ogr.GetDriverByName("ESRI Shapefile") ds = drv.Open(inData) if ...
2
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2answers
51 views

Duplicating polygons in Layer using ArcPy cursors?

I am trying to Duplicate some polygons in the same layer with the same attributes, But it will duplicated them with Null Geometry, i have tried getValue() method, but i got error import arcpy ...