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

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1answer
378 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
252 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
votes
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
votes
1answer
138 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
900 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
181 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
109 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
215 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
758 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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3answers
627 views

How to add an image to an existing data frame using Python?

This is the first time I am using Python on my own, and I have searched for this answer for a few hours with no luck. I am wanting to take a .JPG image and put it in a data frame. The image has to ...
2
votes
1answer
84 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 can'...
2
votes
2answers
406 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 '...
2
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2answers
964 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
886 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
302 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
577 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
votes
1answer
350 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
votes
1answer
417 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
614 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
votes
1answer
355 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 ...
2
votes
2answers
840 views

Script to extract UTM Zone using Range and Meridian information

I am looking for a python or php script that will accept the Range and Meridian values of a location and use it to identify the UTM zone. I have a table that comprises of Easting, Northing, Range and ...
2
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1answer
1k views

Importing QGIS core into Python on OSX

I am interested in learning how to write standalone scripts using QGIS. An answer to my previous question directed me to the PyGIS CookBook which has the following instructions for importing the ...
2
votes
1answer
489 views

How to implent a “maketrans” python function on field calculator

i'm traying to implent python string translate function at field calculatore http://www.tutorialspoint.com/python/string_translate.htm in order to fix hebrew imported from cad. here is the code - def ...
2
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1answer
304 views

How can i include program form (created in Designer ) to my QGIS plugin?

How can I include a form created in Designer in my QGIS plugin? And how to get controls values (textbox,label,etc)?
2
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1answer
260 views

Converting 2D shapefile to Equal Area Projection?

I have thousands of shapefiles with coordinates in lat/long (-180 to +180 x, -90 to +90 y), that contain polygons of which I wish to calculate the area. I'm using the Python GEOS/OGR/GDAL API. If I ...
2
votes
1answer
221 views

Why isn't this Python calculation working correctly?

I want to label the source files for a unified shapefile, and there are three respective columns for each. If there is no value in the column, there is no data from that source; if there is a value in ...
2
votes
2answers
174 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 ...
2
votes
2answers
619 views

Convert Georeferenced imagery to vector data using python

Are there any opensource tools I could use to take a projected georeferenced image such as a jpg with world file, that is UTM projection such as NAD83 and convert it into distinct vector polygons ...
2
votes
1answer
868 views

Looking for a pure Python method to convert Lat/Long To MGRS

Does anyone know of any packages out there that implement a pure python method to convert lat/long coordinates to MGRS coordinates? PyPi has a package, but it requires some c-extensions from ...
2
votes
1answer
5k views

How to create a list and append objects to it through a loop

Still struggling with this script. Now I need to create an arpy.AddMessage that says "Projected: with the list of feature classes that were projected in the loop" i.e. Projected: filename, ...
2
votes
1answer
11k views

Python :ImportError: DLL load failed: The specified module could not be found

I am working on Python plugins for QGIS. I set my variables as PATH :=C:\OSGeo4W\apps\qgis;%PATH% PYTHONPATH:=C:\OSGeo4W\apps\qgis\python But when I try to run my .py file in IDLE I get an error ...
2
votes
1answer
154 views

Locate DTEDs from one layer that intersect a polygon in another layer

I'm new to the GIS world, and using ArcGIS 10, so please forgive me if this is a simple question. I have DTED files (level 2) that I have placed into a mosaic dataset, and I'm trying to determine ...
2
votes
1answer
456 views

Search Raster Files from Folder that Have Same Spatial Coordinates Using Python

I have approximately 700 raster files in a single folder and I need to find files that have the same spatial extent and copy to a different folder. The raster files measure daily snow cover and ...
2
votes
2answers
822 views

Convert CSV files into OSM with FME

I have a database which i've exported as individual csv files for each table. Below are some of the attributes which exist from two of the csv files: wayPointID linkID order x y z length ...
2
votes
1answer
566 views

How to determine area of pixel in meters with GDAL and Python?

I have a raster loaded in Python using GDAL bindings. I'd like to be able to determine the area of a pixel in meters although I'm not confident that the projection is in meters. On this page I see a ...
2
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2answers
1k views

Mapnik TextSymbolizer showing nothing above OpenStreetMap base layer

I'm trying to use Python to create a TextSymbolizer to display a trail name above the trail LineSymbolizer. Below this layer is the OSM base layer which contains its own data for that trail. I can ...
2
votes
1answer
3k views

How to update feature class by iterating through values with branching?

I'm really struggling with getting this to work. Basically, I want my script to get the "newID" value and use that as a look up value. If the "newID" is found in the OldID list then do one thing, ...
2
votes
1answer
592 views

How do I group layers in Mapnik?

I might be thinking about this all wrong, but right now I'm using Mapnik's OGC Server, and using that WMS with OpenLayers. How would I group multiple layers (say country, water, state borders) into ...
2
votes
1answer
514 views

Accessing MPS Atlas from Python with ArcPy?

I'm having trouble finding documentation on accessing MPS Atlas features using python in ArcGIS 10. I need to be able to modify dataframe manager properties, swap map sheets, etc. Is it part of ...
2
votes
1answer
24 views

Python to create new fields in many layers / QGIS

I have a number of line layers on which I need to perform the same task: add 4 columns with the start and end points of each line. The expressions that I use to do this are: $xat(0) $xat(-1) $yat(0) ...
2
votes
1answer
63 views

How to get attribute values from vector features visible in the qgis canvas

I have a vector layer (grid). Currently I select some tiles with the select tool and paste some python code to get information about these features. layer = qgis.utils.iface.activeLayer() ...
2
votes
1answer
62 views

Update raster color ramp with new min/max values using python?

For a script, I want to update the exsiting min and max of a colour ramp with a new one. In the image you can see what I want to update. To do so I tried to follow this thread. I tested the ...
2
votes
1answer
24 views

How to include QgsRasterBandStats in plugin

I'm making a plugin were i want to get the min and max value of a raster. When i tried the following code in the qgis python console it worked fine but in my plugin code i get the following error ...
2
votes
1answer
34 views

How to use create a plugin that contains a set of processing scripts using Qgis Script feature?

I have some script that I would like to share easily. I have read here that its possible to create a plugin using a set of scripts using "Scripts/Tools group in the Processing toolbox, double-click ...
2
votes
1answer
50 views

Cannot update GDAL on Ubuntu

I am trying to use GDAL_Rasterize and found a link via Google that suggested that there were bugs in older versions. I am running Ubuntu 14.04 LTS and 'gdalinfo --version' gives me 'GDAL 1.11.2, ...
2
votes
1answer
50 views

How do I use geometry object in processing.runalg()

I am trying to clip a polygon (large road network) with every row in another polygon (district polygon) using PYQGIS. layer_adm_level = QgsVectorLayer(base_path + adm_level + ".shp",'adm_level','ogr'...
2
votes
1answer
47 views

Python module pyGTiff aligning data

I have been working with pyGTiff for a while and it works great. However my gis data does not have the same projection and extent. I saw that in the repository a a jupyter notebook with a test ...
2
votes
1answer
45 views

Parameters for osm2po web service to route for walking

I have started the osm2po web service using the jar file. In the configuration file, I could see different parameters related to walking but not sure what each one does. I am trying to call the web ...
2
votes
1answer
105 views

Accessing GPS from QGIS 2.14.1/Python 2.7 /Windows10

I would like to access the device described at QGIS live GPS tracking /recommended hardware (GPS USB stick) via QGIS/Python. A gps module does't seem to be part of the standard installation of python ...