Questions tagged [python]

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

Filter by
Sorted by
Tagged with
3
votes
2answers
397 views

How can I read the settings for the QgsPaperItem from XML?

I saved a template qpt for the map composer and now I want to read all the settings. I am able to insert the items with composition.addItemsfromXML... But this doesn't load the settings for the ...
3
votes
1answer
457 views

How to add Real Attributes to Shapefile using pyqgis?

I created the Qmarxan plugin using the fTools plugin as an example base. When I create a new shapefile using the QgsVectorFileWriter function I don't have any difficulty specifying a "Real" field with ...
2
votes
4answers
6k views

How to connect the selectionChanged signal with pyqt?

I am developing a plugin for QGIS in Python, I need to connect the sselectionChanged signal emitted when a feature of the layer is selected, I could not find any examples on internet, here is what I ...
3
votes
1answer
499 views

iterating and exporting all combinations of features as shapefiles

I am trying to export individual shapefiles of all 2 pair combinations from a multi-feature polygon shapefile. To explain this better as set of FID's 0, 1, 2, 3, 4 would be exported as individual ...
4
votes
3answers
10k views

Add feature layer to display with in a script tool for desktop mapping 'App'

The point of this question is to find a way to programatically change the map extent based on user input. My method involves creating a Feature Layer & Selection, but if you have another (...
4
votes
1answer
518 views

geodjango slowness and debugging

I'm using geodjango + postgres to display polygons from tigerline on a map. Pretty simple stuff so far. My issue is that when I use the GPolygon object: django.contrib.gis.maps.google.GPolygon there ...
3
votes
3answers
3k views

Qgis Python code library documenation.

I'm looking for python documentation for specific operations in the Qgis python console. I know there is no suggestions simular to Arcpy but I would like a pure list of operation code lines as "layer....
1
vote
1answer
2k views

arcpy.Delete_management not deleting

I'm struggling with deleting an mxd in a for loop. My code is: import arcpy, glob, os, datetime, time from time import strftime for filename3 in glob.glob(os.path.join(folderPath, "*.mxd"...
1
vote
1answer
1k views

Index out of range error when cleaning up variables

I'm running a script that parses points from a flat database structure into individual feature classes with related tables. A search cursor runs through and stores each field's data in a variable ...
5
votes
3answers
2k views

Using threading module with Arcpy: Manager/Worker architecture

I asked this question on Stack Overflow on how to setup a manager/worker scenario. But I am getting some error when trying to use threading on my Python install with ArcGIS 10 (just the python ...
2
votes
1answer
508 views

Use arcpy.SearchCursor with raster

How can I efficiently subdivide one raster into multiple rasters using the arcpy.SearchCursor? For example if I have a slope and I was to subdivide into 3 rasters: slope1 with values between 0 and ...
2
votes
0answers
182 views

Are there Plugin Compatibility Issues between QGIS 1.6.0 and 1.7.4?

I've been working on a QGIS plugin on Quantum GIS 1.6.0 Copiapo with Python 2.5 that calculates additional values for eachf feature of a vector layer and adds them to the .dbf. We've just upgraded to ...
11
votes
4answers
15k views

How to import qgis.core to Python app?

I'm new to Python. I want to create GIS app with Python using QGIS library on Window 7 64 bit. The way I do: install QGIS 1.7.0 I set PYTHONPATH=D:\Program Files (x86)\Quantum GIS Wroclaw\apps\qgis\...
8
votes
1answer
810 views

How to get rpy2 for QGIS on OSX?

I am a new QGIS user, have installed QGIS on a Mac running Snow Leopard OSX 10.6.8 following all the instructions. QGIS seems to work well for everything other than when I boot up I get the message "...
0
votes
1answer
3k views

How to find Q in m3/sec from a raster having Q in mm for hydro power calculation

I am having a raster file with runoff depth Q in mm which was obtained from SCS method. I want to calculate hydro power potential at any location on my DEM. In the formula Q is in m3/s but we are ...
1
vote
3answers
3k views

How to extract a rectangle corner coordinate in Python script

I want to extract a rectangle corner coordinates of a shapefile in Python script... please suggest me a solution.
5
votes
1answer
4k views

Error getting while creating new field to a shapefile table

I am getting the error for following code to add a new field to a shapefile table. from osgeo import ogr # Open a Shapefile, and get field names source = ogr.Open('my.shp', 1) layer = source....
3
votes
1answer
939 views

How Can I Calculate Time from Coordinate?

For my application I am searching for an API or an algorithm for clicking point time and time zone. I dont know how I can do this but after getting time I want to calculate giving coordinate sun rise/...
2
votes
3answers
17k views

Using if/elif/else statements in ArcGIS Field Calculator?

I have no experience with Field Calculator in ArcGIS 10. I have a very simple calculation I would like to perform that I could do easily via pure SQL but just can't seem to get my head around it in ...
2
votes
2answers
374 views

What are my hosting options for an app that needs tilestashe along side a django app?

I'm building a GIS webapp that uses tilestache to serve MBTiles and a django app to serve geoJson. I'm having trouble understanding exactly what kind of setup I'd need to host this. I'm new to server ...
3
votes
2answers
2k views

Running Different Versions of ArcGIS and Python?

As we know, there are few versions of ArcGIS (9.x,10) and Python(2.x,3.x) are in use. Issues are facing when we run scripts/toolbox of arcgis since the script written in one version of python and the ...
6
votes
1answer
2k views

Wrap GEOS functionality into python

I've been looking on how to get GEOSExtractLine available in python. I looked into Shapely source to if it was available for it, but it's not. I'm trying to wrap this funcionality into Django, much ...
2
votes
1answer
744 views

How to switch to a GDB created in the middle of a script

EDIT: Here's my full script and hopefully a better way of explaining what I need done: #Import import arcpy, sys, os # Set environment settings arcpy.env.workspace = sys.argv[1] inFiles = sys....
0
votes
1answer
1k views

Trying to make xml data readable for Arcgis

I am trying to convert xml data into tabular form for the process of geocoding. We have the xml file with info that we are going to run through an address locator. Do I need a script for this? Can ...
2
votes
0answers
359 views

Recalculate Quantile Breakpoints in CalculateField_management loop?

I have a program that iteratively replaces a temp field where I choose a certain symbology (color ramp and quantile color break methodology) with a few other fields from a join. The program works in ...
2
votes
1answer
1k views

Attribute Table Decimal Places

As we all know, the attribute table field properties has number format to display number of decimal places to up to maximum 15. If we have many fields/columns in attribute table, how can we change all ...
18
votes
9answers
8k views

how to overlay shapefile and raster?

I have a shapefile with polygons. And I have a global raster file. I want to overlay the shapefile's polygons onto the raster grid and calculate the mean raster value for each polygon. How can I do ...
2
votes
2answers
1k views

Using r.mapcalculator and Python

I've been trying to write a script creating binary maps: a=raw_input ("enter a threshold") b=float(a) grass.run_command('r.mapcalculator', formula="**'base_map'>=b**", outfile='map'+str(a), ...
3
votes
1answer
885 views

Removing duplicate features in PyQGIS

I'm trying to remove duplicate features from PyQGIS. Manually I can do it by using "Edit -> Merge Selected Features" and then "Multipart to Singlepart" from fTools in QGIS, but can this functionality ...
2
votes
2answers
180 views

Exposing ArcInfo level liscenses to ArcView desktops via ArcGIS Server and custom python script tool

I have a script that uses an ArcInfo level tool. The script works great on my machine but uses an ArcInfo level tool which the ArcView users don't have. Is exposing these ArcInfo level tools ...
4
votes
1answer
3k views

How do I change a raster's geotransform with GDAL?

I'm trying to use GDAL to set the geotransform of a new raster that I've created by following the steps outlined in the GDAL API Tutorial. # create the new dataset driver = gdal.GetDriverByName('...
7
votes
1answer
1k views

How to attach GP script tools, standard tools, and Python script to a toolbar?

I need to build a custom toolbar that can launch the following items: A Python script tool - shouldn't be a problem, as you can already attach these to a toolbar Out of the box functions such as the ...
5
votes
1answer
2k views

Bing's geocoder with GeoPy not returning a zipcode

I'm just getting started with GeoPy and have been running some tests to determine the quality of the different available geocoders. I have noticed that Bing's geocoder is more accurate than Google's (...
3
votes
3answers
2k views

Tracking change with ArcSDE/Oracle

I'm looking for the simplest way to track changes ([delete, update, create] feature(s)) made to the DEFAULT version of a given feature class in ArcSDE(10) and Oracle(11g). Qualifier: I am not a dba ...
7
votes
4answers
4k views

Spatial Query from PyQGIS?

Is it possible to reach the Spatial Query plugin functionality in QGIS from a Python script (PyQGIS)? If so, how do I accomplish this? Haven't found any documentation for it, even in the C++ API docs.
4
votes
1answer
1k views

Using ArcPy for Copy Parallel, Move, etc (from Editor toolbar)?

Since VB can activate the Editor, then use the tools listed in the Editor, such as copy parrallel, I am wondering whether Python can do the same job? I have been searching the website all day. Still ...
8
votes
1answer
2k views

Add layer to open mxd using ArcObjects from outside the map document crashes ArcMap

I have an Access database (MS Access 2010) that allows users to enter a variety of land treatment information including associated points, lines, or polygons which users can select and the database ...
2
votes
0answers
831 views

Large point to Polygon by buffer-join-buffer-dissolve issues

I have a few large datasets (about 10 million points) which I am buffering, then joining, dowgrading and finally buffering and dissolving. This is all in a model which works fine with sample smaller ...
2
votes
2answers
2k views

GDAL Clipping (hack)

I am trying to use the python script from http://www.sparkgeo.com/labs/2010/07/07/gdal-clipping-hack/ to clip a raster based on many shapefiles. The script is using a mysql database an i would like to ...
30
votes
5answers
7k views

OpenSource Remote Sensing Tools for Classifying Roofs

with envi image processing and classification tools, you can get roofs from images with some spectral value and then you can convert it some vector data for your app. in python with OpenCV which have ...
3
votes
4answers
16k views

Parse XML files in Python (ElementTree)

I am trying to parse some xml and rss feeds to extract some of their data in order to store it in a PostGIS database. The file I want to parse is here: http://earthquake.usgs.gov/earthquakes/catalogs/...
3
votes
3answers
3k views

Error installing GDAL 1.9.0 python package

I'm trying to install the GDAL python package in a python 2.7.1 environment on RHEL 5. I am using the command 'pip install GDAL'. I have no problem installing other packages like numpy, etc. in this ...
0
votes
1answer
812 views

Generate a random 100x100 m bounding box in any projection in pure Python?

I'm given: Extend of WMS Layer SRS Now I want to, in standard 2.6 Python (no OGR or C lib dependencies), to generate a 100x100m random bounding box within that extent (assuming it is more than ...
1
vote
1answer
1k views

Dynamic Text in ArcMap 10.0 and arcpy - getting user name in specific format

I need to put in a specific text into a text element. The initials of the user who built the map. With arcpy I am trying to set the text element with dynamic text. If I put <dyn type="user"/&...
1
vote
0answers
891 views

How do you convert a bounding box into the canvas CRS?

I need to convert the pixel coordinates of a bounding box to the same CRS being used by an existing layer. Here's the relevant code so far: # First, get the layer-coords version of the bounding box: ...
6
votes
2answers
2k views

Creating geodatabase from CSV using python

I have a file with weather data (daily) for multiple weather stations for multiple years. I am looking for some python script to automate the database creation process and its interpolation on a daily ...
2
votes
2answers
2k views

With Python and ArcGIS, how do I add features to a featureclass?

In ArcGIS Python code: CopyFeatures_management copies features to the same featureclass - that means overwrite to the feature class. How can I add new features to one featureclass or namely different ...
16
votes
8answers
34k views

How to get X Y coordinates and cell value of each pixel in a raster using Python?

I'm really new to Python and I would like to know whether there is a quick method to get cell values of a raster pixel by pixel and the coordinates (map X Y coordinate of centre of each pixel) using ...
1
vote
1answer
477 views

Is Django's LayerMapping capable of putting a static value into all features?

I'm using GeoDjango's LayerMapping utility to try and import a set of features. The catch is that aside from the attributes in the source layer, I want all the destination features to have the same ...
7
votes
2answers
3k views

Python: How to export Shapely objects to DXF file

Using shapely package for Python how to export the resulting shapely objects such as buffer to a DXF file?

1
164 165
166
167 168
173