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

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128 views

How to analyze and combine overlaping elevation maps into one?

I have 30 overlapping maps that contain tree density heights (measures between 1-100%) of a large area, and I need to get the highest point by pixel and create a new map with all these highest points ...
2
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2answers
48 views

Assigning ID to features with similar attributes

I have a polygon feature with three attribute columns. The values in each of the attribute columns are number coded. I want to generate an ID (fourth column) for the unique combination of the values ...
2
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1answer
892 views

How to create a symbol with graduated marker size and line width in pyQGIS?

I am using QGIS + pyQGIS + Python. Layer geometry is line. Each line has a magnitude and a direction (from 1st node to 2nd node). What exactly I want to perform is "graduated width marker symbology ...
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2answers
873 views

Find index location of a lat/lon point on a raster grid in ArcPy

This question has been confusing me for a while, and I'd love y'all's help. I'm trying to find the index location on a raster (in terms of column and row#) of a specified lat/lon point. My first ...
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1answer
436 views

How to assign values to field using if/then logic involving multiple fields?

I want to run a field calculation on a string field named [territory] that first looks at a string field [majr_src] to see if there is a value other than "NONE", if so [territory] = [majr_src]. If ...
2
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1answer
948 views

How to refresh Catalog window from ArcMap using Python?

I am running my script from ArcMap and I have the Catalog window open on the side. I delete some extra files in the end of my script but I have to refresh the Catalog window to see them go. So I ...
2
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1answer
922 views

ArcGIS 10.0 get sde information out of .mxd

The overall goal here is to iterate through several directories of .mxd files and document which SQL Server instance of SDE they are pointing to, with the database name and feature class names. All ...
2
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2answers
78 views

Accessing features via arcpy

i try to use arcpy to accessing the features of a shapefile. I tried to use a searcheCursor, like that: cursor = arcpy.da.SearchCursor(Points, ["SHAPE@XY"]) for row in cursor: x, y = row[0] ...
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2answers
854 views

Interpolation iteration using ArcGIS- arcpy

My current project requires interpolation of state level weather data. Approximately 5 years of daily data needs to be interpolated. I still need to figure out the best interpolation method. However, ...
2
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1answer
331 views

How to add ArcPy Feature Layer to ArcMap automatically?

With Python, how do I get either the MakeXYEventLayer_management or the MakeFeatureLayer_management layer that is temporarily created added to ArcMap automatically after the tool is run, without using ...
2
votes
1answer
319 views

Model or Code to query all feature classes in geodatabase by selecting by attribute

I have a geodatabase that has 60+ feature classes that each contain records for 60+ locations. I need to export all records from each feature class for a specific location. In each FC there is a ...
2
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2answers
352 views

Group and export to pdf based on an attribute field using DDP - Python Script

Using Python, I want to export a map series. Each series needs to be grouped based on an attribute field which is not being used in DDP settings (page num, page index etc...). For example: my ...
2
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1answer
156 views

GDAL local files VS ftp files

I can successfully get raster information when the raster file is located on my local file system: import gdal from gdalconst import * filename= "MOD11A1.A2012193.h11v11.005.2012196013534.hdf" ...
2
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1answer
897 views

How to import sextante(processing) for QGIS 1.9 (2.0)

In the current QGIS development snapshot the SEXTANTE toolbox has been merged into QGIS and is now known as "processing". This is a good step, but the previous import command doesn't work anymore. ...
2
votes
1answer
73 views

arcgisscripting in CGI script

I'm trying to write a Python script that imports arcgisscripting (stuck on 9.3.1 here) which is then run as CGI by a web app. It runs fine from the Windows command line but as soon as I drop it into ...
2
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1answer
565 views

OGR: How to save layer from AttributeFilter to a shape filter?

I select a subset of features from my shape file like so: node_lyr = nodes.GetLayer() q_str = "%s = %i" % (field, value) node_lyr.SetAttributeFilter(q_str) What is the best way to make a shape file ...
2
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1answer
200 views

Using Sum() or something similar with CalculateField_management and FieldLists

I need some help with using variables with CalculateField_management tool. I've tried several different scenarios but don't seem to have any luck. What I have is a list of fields containing water ...
2
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1answer
119 views

How to set default bad layers handler in the python plugin?

I am trying to write a python plugin for QGis. My python plugin will copy a template qgis project into data catalog with ESRI shapefiles. Because data catalogs can vary in its content there will be ...
2
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1answer
400 views

Using update cursor on a field with a domain

I have been replacing field calculations with python update cursors in many of my work flows and today I ran into a problem. The fields being updated have an attribute domain. so now, when I ...
2
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1answer
330 views

Can I append to different tables using ogr2ogr?

I have been through many related questions and links but I am still confused as to how/if this is achievable. So, I have defined tables in my postgis database and I would like my ogr2ogr commnand to ...
2
votes
2answers
243 views

Why does QgsSpatialIndex::nearestNeighbor(point, 1) sometimes return 2 lines?

I'm trying to get the closest line to a point using pyQgis in a plugin. The active code file is this: http://pastebin.com/TDzmsKVM When I request the closest line (only 1) nearestIds = ...
2
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1answer
437 views

ImportError: No module named qgis.core

I am on Ubuntu 13.04. I get the following error message - Traceback (most recent call last): File "analyse.py", line 1, in <module> from log import shelve File ...
2
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1answer
470 views

how to loop grass command in python and put variable in output file

first day Grass programming with python scripting; first prob; simple I want to reclass the same raster several times; and save the file with the value loop variable at the end ... can not get it ...
2
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1answer
417 views

How to set a spatial filter with Python/GDAL?

Is there a way with GDAL (Python) to set a spatial filter (bounding-box) on a raster before I process it? I want to read it as an array. BandReadAsArray(band, xoff=0, yoff=0, win_xsize=None, ...
2
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1answer
739 views

Combining polygon geometries with python and QGIS segfaults

I am trying to combine polygons, using Qgis 1.8, and every time I run this script in the python console, I get a segmentation fault. Here is the script: from PyQt4.QtCore import * iface = ...
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2answers
978 views

Geopy Error with Reverse Geocoding

I am using Geopy. I get following error for the code. I have using the same code as on https://code.google.com/p/geopy/wiki/ReverseGeocoding from geopy import geocoders g = geocoders.GeoNames() ...
2
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1answer
639 views

Python code: Using Search Cursor to find missing values in attribute table between two layers in one MXD

I need help! I am writing a program that will look through the table of a station layer and then go to the annotation layer and list all the missing values. For Example: The station layer has a field ...
2
votes
1answer
2k views

Incorrect field name resulted in RuntimeError: ERROR 999999 (Also, better code for adding and calculating fields)

This is the bottom half of my code (and it's been edited somewhat to share publicly). The code works perfectly fine when the fieldList has only three fields in it, but when I populate it with all 108 ...
2
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2answers
218 views

How to create a line from more than two points?

I have a loop which calculates two points for each iteration (x3,y3) and (x4,y4). As seen in the code these two points are added for each iteration, which gives i-1 lines. Each line has a individual ...
2
votes
1answer
779 views

Spatial Join Python Command to summarize attributes

I am trying to run the Spatial Join function through the python shell in ArcGIS 10. When you do the point-and-click method of spatial join, you are given a tool window with an option that asks "How ...
2
votes
1answer
364 views

Mysterious Invalid Syntax in Field Calculation

I'm trying to calculate a field in Model Builder using the Calculate Field tool. I'm using the following code block and expression in the calculation, but am getting an "invalid syntax (, line 1)" ...
2
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1answer
243 views

Select and zoom python script

I am attempting to make a simple select and zoom python script for my address points. Currently the script will complete successfully but will not select or zoom to the entered point. I am using two ...
2
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2answers
2k views

How to make editable polygons in Google Maps?

I've just recently started learning Google maps, JavaScript, etc., and have a few questions about a project that I'd like to do. I'm wanting to take some ESRI shapefiles, convert them to KML, and then ...
2
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1answer
134 views

What is causing sr.lock on tables after looping?

The following code puts an sr.lock on each table in my List. What’s causing my tables to lock up? I understand my script is reading or opening my tables temporarily to perform the ...
2
votes
1answer
863 views

Using Python in the Field Calculator, how do I refer to a field in another shapefile?

I want to compare the changes in geometry between two shapefiles (of election districts in NYC. One is from 2001 and the other 2005). I am attempting to calculate a new field in the 2005 shapefile ...
2
votes
1answer
175 views

How to get a list of all projections that are currently available in QGIS via the PyQGIS-API

i'm building a QGIS-Plugin and i want the user to choose a CRS out of a combobox in which the coordinates he would enter into some textfields are represented, so these can be converted into another ...
2
votes
1answer
99 views

Python code for locking elements in Layout view

Is it possible to lock elements in layout view in Python? I know it is possible in the production cartography extension from ESRI but all I need is the funcionality to lock elements. I am wondering if ...
2
votes
1answer
211 views

Dissolving stream orders using Python rather than VB script?

I've been trying to dissolve streams, using orders programatically and I came across this VB script. The reason is that if I use ArcGIS dissolve, it merges the confluence of the same orders. I would ...
2
votes
1answer
722 views

Update Layer with python, error attribute renderer

I am attempting to automate symbology using python, and ArcMap 10.0. I am importing this script into a toolbox, which I run from arcmap Currently I am getting two errors: 1) LayerObject: Set ...
2
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1answer
82 views

remember QGIS instance

it would be absolutely great if someone could help me with the following problem: I have a simple Python-Plugin that starts another executable in a subprocess. From within this application (which ...
2
votes
2answers
402 views

arcpy.mapping.AddLayer invisible layer

I'm having a bit of a problem with a script on a particular machine. ========================================================== import arcpy,sys class AddLayer(object): ''' classdocs ...
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2answers
893 views

How to import qgis.core to python IDLE?

I try to follow the step in How to import qgis.core to python app? to import qgis.core with Python Shell. But when I type set PYTHONPATH=C:\Program Files (x86)\Quantum GIS Wroclaw\apps\qgis\bin it ...
2
votes
1answer
836 views

How to add a progress bar to a python plugin?

I would like to add some type of progress bar to my Qgis python plugin. Can someone point me to an example?
2
votes
1answer
292 views

Count the number of symbols in a 'new symbology' renderer from pyqgis

Background : I create a lot of symbology using 'saturation' ramps - for want of a better term, e.g. where the hue and value of each symbol stays the same, but the saturation changes. I couldn't figure ...
2
votes
1answer
552 views

Multiprocessing error in QGIS with Python on Windows?

I have this error when I try to use Manager() from python multiprocessing library. (Just start QGIS open Python console and execute the two following lines) >>> import multiprocessing ...
2
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1answer
339 views

How to get all attributes from a non geometry PostGIS layer with Python in QGIS?

I want to extract all attributes from a non geomety layer in QGIS with Python, but there is only the function uniqueValues(fieldIndex) More specific: I have a postgresql table which is loaded into ...
2
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1answer
406 views

Python script for Data Driven Pages to run a series of DDP at once?

I have a several different polygon shapefiles that I am using to create individual maps for each polygon within the shapefile. The layout is the same for each map, the only thing that changes is the ...
2
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1answer
599 views

Script for Editing TIN in Arcgis: modelbuilder works, when exported as script gives an error

Arcgis can give such a headache! I want to automate loads of small tasks, and so I need to edit empty TIN with python in order to create a full TIN. My srcript is giving errors, so I tried by hand to ...
2
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1answer
340 views

Is it possible to set a layer style (e.g. set the color ramp) before loading the layer using pyQGIS?

I am implementing a tool which allows an user to calculate some statistics with some data from the registration office. My question is, can I set some layer styles using pyQGIS? The analysis part is ...
2
votes
2answers
1k views

Conditional combining of multiple rasters to produce one output using Python?

I have two rasters for same spatial extent and need to compare both rasters cell by cell and produce one output raster. Each has 10 land cover classes. Based on those 10 classes the comparison should ...