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

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Clipping Buffers

I have buffered a line shapefile where many lines are intersecting but not broken at intersections. I am trying to select each record in the buffer file and clip all intersecting polygons in the same ...
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2answers
736 views

Create point geometry in a feature class with all the attributes prepopulated

So here is the problem. I have a text file with space delimited values. A standard text file with the headings separated by spaces and then on each next line values for these headings (columns) also ...
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2answers
2k views

Delete feature selection using Python (ArcGIS 10)

I'm having some issues with a Python script for ArcGIS 10. The idea is to delete points from a single shapefile according to the values of two columns ("Tracks" and "Tracks_1"). Therefore, I want to: ...
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1answer
2k views

Speed of editing attributes in QGIS from a Python plugin

I'm trying to edit the value of an attribute for each feature in a layer using a QGIS Python plugin. I've found that doing this outside of editing mode is much slower than while editing (even ...
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2answers
695 views

upload table to ArcGIS Server

We are building a process which will allow users to submit a table of GPS data to update our central repository for all GPS data. Let's say that the target is simply a SQL data table. At first I ...
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1answer
605 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 ...
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2answers
2k views

Using Python to parse an XML containing GML tags

I am trying to write a python script which pulls GML tags out of an XML file and formats them into WKT for inserting into a PostGIS database. I have been successful in doing so for an XML containing a ...
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3answers
4k views

How to replace non-English characters in attribute tables using Python?

I have a few shapefiles where some of the attributes contain the non-English characters ÅÄÖ. Since some queries doesn't work with these characters (specifically ChangeDetector), I tried to change them ...
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3answers
2k views

Interacting between Openlayers and Python

I have a openlayers website like this one that gives the user the ability to draw polygons and then creates a GeoJSON file. I want to process this GeoJSON with a python script. The python script ...
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97 views

Create Vertex and add empty attributes to it

How can I create a vertex(and then a point feature on the vertex) on a polyline and give it some empty attributes(create fields), move an existing vertex, delete vertex? I am in ArcGIS environment and ...
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1answer
2k views

Pros and cons of using Ruby/Rails/RGeo or Python/GeoDjango for a web based GIS

We're at the investigation phase of creating a web based GIS. We're assessing options for an ORM to use in all of our backend import/export and processing routines. From my research, GeoDjango appears ...
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1answer
223 views

Why do ECWs go missing when exporting MXD to PDF with ArcPy?

I'm trying to export some MXD maps to PDF with arcpy (ArcGIS 10.1). Everything works fine and dandy except for ECW images, which don't appear in the PDF. However, when I execute the same code from the ...
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76 views

How to identify grid shift file used by osgeo in Python?

I wrote a Python script reprojecting points from a source coordinate reference system (SCRS) to a target one (TCRS) both identified by an EPSG code. I would like my python script to retrieve details ...
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1answer
400 views

OGR - Weird GeomType -2147483645 on polygon shapefile

I am trying to import a shapefile (multipolygon) in an app with ogr but I got an error about invalid geom type. If I inspect the data with ogr like this: datasource = ogr.Open("c:\\temp\\data.shp") ...
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1answer
150 views

Join multiple shapes in a workspace based on a common field

I’m completely stucked!!! I’m working with meteorological data (wind) but I have to arrange the data for a program to be able to process it. I have text files, two per day (one with the wind direction ...
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1answer
191 views

How to query and display layer using ArcGIS Python script tool? [closed]

I have database which contains point shapefiles and raster files for 3 species. My aim is to develop a script tool that should have a search tab to enter the species name. also, a check box to select ...
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1answer
308 views

How come “Zoom to Polygon” always puts me in the middle of Nebraska?

This is an issue related to this question I'd asked a few days ago. I've got that code working, to an extent. Every time, though, that I double click on one of the Polygons in the attribute table that ...
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1answer
246 views

How can I change SQL query through a layer of an action (python)? [closed]

I have three layers from three diferent database tables. When I click in other layer I want to change (with an action) the query of that three layers. How can I do that? Thank you
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2answers
718 views

What are mystery green lines in Layout View produced during ArcObjects script execution?

Could any of ArcObjects guru tell me, what are these green lines on my Page Layout and what to do, or not to do, so they do not appear? See image attached. I do used ArcObjects from Python. My script ...
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3answers
837 views

How to create Where Clause from user input via Python list?

I am trying to perform a query based on values in a Python list. The where clause will then be used in an Update Cursor, so that the rows NOT equal to the values in the list will be deleted. This is ...
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4answers
991 views

Get vector features inside a specific extent

The problem: I have a very large vector layer with many features and a much smaller raster layer in a defined region. I want to get only those vector features which are within the raster layers ...
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1answer
116 views

How to reopen a plugin-window in QGIS?

I am currently taking my first steps in playing around with programming a plugin in python 2.7 for QGIS 1.8. While my plugin does what it should, I would like to make it more userfriendly. At the ...
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1answer
165 views

How to change VB syntax to Python in Field Calculator?

I want to calculate a field, this is my working example in VB: "C:\Users\Admin\Desktop\Data\" & !Work! & "\1000_\" & !Data! & ".pdf" I'm slowly changing all my scripts to Python, ...
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0answers
16 views

Sextante Modeler Error “global name os is not defined” [duplicate]

I want to generate a model whic reclassify radter values. So i added Saga reclassify grid values tool to Modeler and saved the model. When i run the model i got this error both on Ubuntu OSgeolive 6.0 ...
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1answer
353 views

How to create polygons in ArcMap 10.0 using lat/long data from SQL Server 2008 database?

Forgive me if this is very basic, as I'm new to GIS work (though I've been a programmer for 10 years) and so I'm not really sure how to approach this, but here goes... Can I take a table with ...
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2answers
4k views

How to get raster corner coordinates using Python GDAL bindings?

Is there a way to get the corner coordinates (in degrees lat/long) from a raster file using gdal's Python bindings? A few searches online have convinced me that there is not, so I have developed a ...
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1answer
108 views

Error on rendering linestring

I am using Mapnik 2.0.1rc0 on a Windows 7 with python 2.7 32bits inside a GeoDjango App using xml. The datasource come from spatialite 4.0. My tiling script can render polygon and point features ...
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317 views

mapnik error - fatal flex scanner internal error--end of buffer missed

I am using Mapnik 2.0.1rc0 on a Windows 7 with python 2.7 32bits inside a GeoDjango App. I often got this error: fatal flex scanner internal error--end of buffer missed that makes python to crash ...
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1answer
870 views

Where Clause problems when all parts are user input variables

I have written some generic user ipnut code for a toolbox script (ArcGIS 10.0) but because everything is a variable I don't know how to write the SQL whereclause. Please can someone help and suggest ...
2
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1answer
669 views

Error 999998 in Arcpy 10.1

I found an RuntimeError: ERROR 999998: Unexpected Error when lunching Arcpy in my ArcGis 10.1 such as this: Runtime error Traceback (most recent call last): File "", line 50, in File ...
3
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1answer
363 views

AGS 10.1 geoprocessing service returning the wrong URL

I have an image export geoprocessing service that runs on ArcGIS server 10.1. It works by writing an image out to the scratch folder, and returning the location of that image. Basically just this: ...
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651 views

How to transfer the attributes of features based on their spatial relationship?

I'd like to check if a point feature class is placed on a line feature using python in ArcGIS 10.0. I have created a set of point features and placed them directly on a group of line features at ...
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2answers
392 views

How to determine the coordinates of the corners of the raster layer

How can we determine the coordinates of the corners of the raster layer? The image opens function QgsRasterLayer.
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2answers
164 views

How to interact layers with a nested loop?

I've dealing with the code below with such a long time. I have to show in a raster image the result of calculating the cost of the electricity for a solar plant. The thing is that I have to interact a ...
2
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1answer
492 views

Compare two Digital Elevation Model (DEM)

I would like to know what's the best method(s) to compare two DEMs without using any GUI soft like QGIS or ArcGIS. I'd like to do it in Python or C++, with GDAL or other similar lib. Does calculating ...
3
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3answers
2k views

Updating Attributes using Pyshp

Is it possible to update an attribute field in a shapefile using pyshp ? I went through their documentation and all they show is how to create new attribute rather than editing or updating an already ...
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2answers
441 views

Moran's I z-score in ArcPy

I have a ArcPy script to calculate Moran's I several times (50 to be precise). However, I am not interested in the Moran's I value, what I need is the z-score returned by the tool. Even though the ...
4
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1answer
144 views

How to return text from GP service?

So I've got a website that I want to extend by letting people look up postal/zip codes for an address they enter. I've already got all the addresses (with their postal codes) for the city in an ...
2
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2answers
373 views

Weird File Path Returning from Print Statement Causing ERROR 000732

I have created a python script in ArcGIS 10.1. My first parameter type is a 'Feature Layer' set to as a multivalue input. I was running my script quite well off of data from one of my drives (my ...
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0answers
442 views

Extracting x,y,z values from a postgis linestring to python using ogr

I am trying to load a postgis linestring into python (using ST_DumpPoints) and extracting x,y,z coordinates, which is working but extremely slow..and if i mean slow, i really mean it (yes, it takes ...
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0answers
654 views

How to calculate average value within a polygon(in Qgis with Python)?

Now I have a point and polygon shapefile and I want to calculate the points' average value within each polygons How to do it with python? I tried to find out but google gives me a lot of raster ...
7
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1answer
8k views

Calculate area within Python script in Arcmap

I am trying to calculate the area of a polygon within my Python script. I create a new polygon from merging two together, and I'd like to add the area of the resulting polygon to a field in the output ...
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1answer
133 views

How to save ArcGIS process output to variable?

I've created script in Python for ArcGIS that simplify Line, and make buffer from processed line. input = "input.shp" name = "bord" buffer = "buffer.shp" gp.SimplifyLine_management(name, input, ...
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1answer
189 views

How to save python session in QGIS?

After running a lot of scripts in QGIS' python console, I have more than 10 dictionaries and lists, and I need these for further analysis. Is there a way to save python session, with all these ...
2
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4answers
3k views

Possible to add multiple fields in single arcpy statement?

I'm trying to add multiple fields to a table using arcpy and am wondering if it's possible to have multiple fields declared in the AddField management, and their values, separated by commas or ...
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1answer
191 views

How to save image to disk with with gdal_translate?

I do: import os from gdal import * filename = 'c:/rast.jpg' outputTif = 'c:/rastOut.tif' os.system('gdal_translate filename outputTif') but it returns "1". gdal_translate doesn't save the image ...
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1answer
396 views

How to add MS SQL table using python console?

I have MS SQL Server 2008 R2 database. How to add MS SQL Table using python console in QGIS?
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1answer
272 views

OWSLib and python3

Trying to install OWSlib-master (and 0.7.1) from https://github.com/geopython/OWSLib yields problems that ultimately seem to be related to python3 >c:\Python32\python.exe setup.py install running ...
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1answer
924 views

qgis plugin: “WindowsError: [Error 6] The handle is invalid”

OS: Windows 7 64bit GIS: QGIS 1.8 (qgis.org/downloads/QGIS-OSGeo4W-1.8.0-2-Setup.exe) path variable: GISBASE=C:\Program Files (x86)\Quantum GIS Lisboa\apps\grass\grass-6.4.3RC2 ...
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0answers
298 views

Field calculator error [duplicate]

NOTE: This problem is similar to one that was answered here: Why does Field Calculator return 0 values when decimals are expected? I'm relatively new to python, and am trying to run a simple field ...