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

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How to create a map with states by attribute value?

I'm using Qgis, but I am quite familiar with R and python. So I could use any of these. I want a map of mexico but want to color the stats according to a certain variable. It goes from 0 to 100. So ...
6
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1answer
91 views

How to get info from selected object?

I am new to the Quantum Plugin development and wonder if there is more information about the following. I have added a shape file and am (off course) able to select a point from this shape file. In ...
5
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0answers
185 views

How to rotate polygon to find best fit in Mapnik? [closed]

I have a quite simple problem but somehow I just fail to solve it. There is a polygon and a range xsize and ysize. The x and y size determines the mapnik generated image. The polygon should now be ...
2
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1answer
254 views

Cannot add layer to map in arcpy

This is related to my question ArcPy replaceDataSource, but can anyone explain to me why the following code fails to add a valid layer from a .lyr file, and I get the same problems as in that question ...
5
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1answer
381 views

Can you synchronize tables between ArcSDE(MSSQL) and PostgreSQL(PostGIS) regularly?

I have spatial tables in ArcSDE 10.1 (MSSQL 2008 R2) geodatabases and need to update the same spatial tables in PostgreSQL 9.1(PostGIS 2.0.1) geodatabases. Basically I use my ArcSDE environment for ...
2
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1answer
66 views

Collector cable optimizer

I'm hoping to find some pointers for a project that i'm supposed to be working on as part of a team. We're going to create an extension within ArcMap that uses python to process information within a ...
1
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1answer
131 views

keeping the coordinate system of raster files in the resulting raster file after operation with numpy

I'm trying to read as array two raster files using ReadAsArray in GDAL/python, perform some map algebra operation on it using numpy and then write the resulting raster file in GTiff format using ...
3
votes
1answer
401 views

Problem editing raster and saving with projection and transformation intact

I am trying to make a custom tool to Arcmap using Python. It is supposed to read in a raster DEM, a point shape file and a distance, and output another raster. The output raster should be ...
5
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1answer
504 views

Where can I find GDAL bindings for Python 3.3?

I have been using GDAL 1.9.x on Python 2.7 and took the bindings from here. Is there a place to get GDAL bindings for Python 3.3 or is GDAL not officially supported in Python 3.3 yet?
4
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1answer
1k views

Python script for constructing a WHERE clause from user input

I'm trying to construct a where clause from user input that will eventually be passed through as a SQL statement in the select tool or the select by attributes tool. I've started a script thats been ...
4
votes
1answer
589 views

Using group by to set a PostGIS datasource using QGIS Python API

I am writing a QGIS Plugin and wish to obtain data from a PostGIS table using the Group By clause using something like the following code: uri = QgsDataSourceURI() uri.setConnection('localhost', ...
1
vote
1answer
226 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 ...
8
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3answers
8k views

How to create a button in Arcmap 10 to run a Python program?

I have a script that I want to run within ArcMap when a button in a toolbar is clicked, and so far I have only been able to make the script into a script tool. I need it to run as a command, not as a ...
6
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2answers
754 views

How to add GDAL to existing Python installation?

I would like to download and install GDAL for Python version 2.6 [MCS v.1500 32 bit(Intel)] on win32 that supports reading FileGDB's with Python. But I am not sure how to go about this. I found one ...
3
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2answers
303 views

How to generate Buildings ID numbers inside parcels

In order to decrease manual data entry, I would like to automate a task to generate numbers for all buildings inside a parcel starting with 1. For example, I have 4000 parcels and each parcel has ...
5
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1answer
2k views

How to update shapefile data source in multiple dataframes and mxds using lyr.replaceDataSource and Python dictionary?

After reorganizing the file structure for some of our GIS base data files I need a script to update the data sources for ~ 100 shapefiles in about 50 mxd files. Some of the mxds have multiple data ...
11
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1answer
2k views

How to access feature classes in file geodatabases with Python and GDAL?

I am trying to access a vector dataset in a ESRI File Geodatabase using Python + GDAL. I have successfully compiled GDAL with the file geodatabase API. The FileGDB driver is working correctly since ...
4
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1answer
953 views

book/tutorial on using rpy2 in python for kriging?

I am proficient in Python, but have no knowledge of R. Can you suggest a good tutorial in using rpy2 or any other R library to perform Block/Cokriging "Kriging"
3
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1answer
272 views

How can I put coded domains into a list to be created in python script?

I have a large list of coded domains. They are numbers like: 01.6530.01, 05.7991.08, 05.7991.01, 05.7991.06 The code will be the exact same as the description. I've tried to make a list using: ...
3
votes
2answers
2k views

Getting values from attribute table and inserting another table

I have line feature class of a river network and “FromTo” table. Lines are dissolved so they are not segmented from junctions. I need to write a Python script in ArcGIS to do following: Begin from ...
3
votes
2answers
273 views

Process every 100 records in list

An arcpy merge process is failing due to the size of the datasets and I need to just merge every 100 tiles before it goes on to the next 100 tiles. I wrote the following snippet but it is just ...
8
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1answer
2k views

How to make a new raster using con() script in Python?

I'm new to Python and have been trying to code a raster calculator style script. Basically, I want to convert a raster that has values 0 to -10,000 into a raster that is populated by 1s between ...
2
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1answer
522 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?
8
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1answer
410 views

How to see what lines have changed in an updated Shapefile?

I'm using my county's GIS data to update the roads in OpenStreetMap. I have a copy they published last year and one that was just published, and I'd like to find all the LineStrings that have either ...
2
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0answers
58 views

Is there a way to distinguish between digitized and pasted features?

Is there a way to tell if an added feature in QGIS is in fact a newly digitized one or a pasted feature? I think QGIS is treating both cases in the same way, emitting the same signal: ...
5
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1answer
101 views

Is it possible show the feature attributes dialog when I add a feature in code?

I want to know if it is possible to make the feature attributes dialog in Qgis show up when I add a feature by code using: QgsVectorLayer::addFeature( tFeature ) This is available when I add ...
2
votes
2answers
158 views

How to use model-builder iterator with a custom bit of arbitrary code?

How do I integrate a in-line variable from modelbuilder into a python script? Specifically, I'm using an iterator, and I'm trying to include the 'name' variable in a python script. I believe the ...
2
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1answer
271 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 ...
3
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2answers
598 views

Using 'gdalwarp' in Python script for Grass

I'm writing a Python script that aims to re-project various LANDSAT tiles into a common projection and then import the tiles into Grass. The script at present is shown below: #!/usr/bin/python ...
8
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2answers
527 views

How to add different sized rasters in GDAL so the result is only in the intersected region

I'm writing a Python method that adds two rasters and generates a single raster output. For reasons beyond my control, the extents of the input rasters are different, but they do overlap. Is it ...
6
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1answer
419 views

How to draw shapes with highest possible decimal accuracy

I am trying to read input of lat and long to draw the shape based on condition.The input is standard array of lat and long with 15 decimal accuracy. I am realizing - I am loosing some decimal accuracy ...
2
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1answer
375 views

Convert a List to a file list to use in an arcpy tool

I just can't figure out how to feed a list of files into an arcpy tool... I have List_tif.append(os.getcwd()+"\\Stage1\\"+name+"\\GeoTif\\"+name+"_"+str(ddp.pageRow.PageName) + ".tif;") That ...
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0answers
175 views

zonal statistics in Python crashes

I have a python script that works (it's worked for several other projects in the past and it worked for my current project initially). But whenever I run it, Python crashes sporadically. It would go ...
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0answers
93 views

How to get the geometry of a polyline to a specific precision?

In python, I use point = geom.asPolyline() but it looks like I am not getting any precision just whole numbers? How can I get the geometry and a certain precision?
4
votes
2answers
227 views

FindLabel not Defined

I'm trying to make an advanced label expression using the python parser and I keep getting the following error: def FindLabel ( [Direction] ): return "{}° {}' {}\"".format( ...
2
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0answers
36 views

How can I set python path and version for QGIS? [duplicate]

Possible Duplicate: Couldn’t load SIP Module When I'm starting QGIS I'm getting the problem: "Couldn't load SIP module. Python support will be disabled." And there is also: Python version: ...
5
votes
2answers
1k views

How to improve Python script processing speed (performance)?

I've been working on a script which essentially reads in a large amount of point and polygon data and generates frequency values for a featureclass of 2.5 acre hexes covering California. I have found ...
3
votes
1answer
599 views

How do I programmatically export a single Data Driven Page to JPEG?

I am trying to write a python script to export a individual pages to a jpeg. I am getting the error "PageLayoutObject: Error in SetDataDrivenPageID". Can anyone see where I am going wrong? import ...
7
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1answer
422 views

Migrate python scripts from 9.3 to Arcgis10

What changes are needed to migrate scripts from the ArcGis 9.x environment/gp-object to the ArcGis 10/arcpy environment? Can anyone provide a good overview what the changes are? Can someone share ...
13
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3answers
5k views

Writing numpy array to raster file

I'm new to GIS, and I'm lost with something I feel ought to be relatively simple. I have some code that converts infrared images of Mars into thermal inertia maps, which are then stored as 2D numpy ...
1
vote
1answer
127 views

Selection on Feature layer (geoprocessing)

I have a feature layers with states and counties fields. I want to make a selection tool. Tool dialog should have input for feature layer and two drop downboxes for states and counties. When user ...
2
votes
1answer
363 views

Edit Shapefiles Attribute data in GeoServer Programatically

I'm rendering a shapefile using GeoServer and using OpenLayers library to render it in the web browser. Now I have created the option of editing the attribute data in web browser. I want the edited ...
3
votes
1answer
177 views

How to get raster layer pixels contained in a shape defined in a vector layer

I am new in QGis python plugins dev and I have a "maybe stupid" question (in the title :-) ). I try to retrieve pixels (from a raster layer) which are "contained" in a polygon defined in a vector ...
9
votes
2answers
3k views

Python scripts that run inside ArcMap vs ones that run outside?

I'm just starting to get into Python scripting for work.. I'm currently creating a script to automate a process. Basically, it asks the user the client name, gets a projection if available, creates ...
4
votes
2answers
362 views

How to pass an output stored in a single variable into another script using arcpy

I am running set of processes each with different outputs in a python script. Is there a way to set a variable as global so that just the output of that single step can be accessed from other scripts? ...
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1answer
401 views

Does arcpy have an issue with directory names starting with a number?

I have a script to export DDP extents to tif and when I change arcpy.mapping.ExportToTIFF(mxd,"tests\BA\BA10k_" + str(ddp.pageRow.PageName) + ".tif",df,9306,9306*ar,1800,True) to ...
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vote
1answer
124 views

Extending ArcGIS

I've been tasked with a thesis project where i have to extend the features of ArcGis. I've been asked to create a model written in Python that can run out of ArcGIS 10. This model will have a simple ...
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1answer
4k views

How to convert WMS to SHP?

I'm looking for tool that will be convert WMS to vector layer. Are they ready tool?(for example in python)
4
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3answers
1k views

Copy dbf data into a shapefile in Arcpy

Basically it's to perform a one-to-many join in a python script, from a dbf to a shapefile. I saw (Greg Krakow's method) using QGIS, but I can't use it (I'm working on it, but QGIS is not yet ...
3
votes
2answers
1k views

From text data create a FeatureClass with table with python

I'm searching how the output of one program (text file with some writings, but also with data as numbers, dates, times, coordinates, all separated with commas) can be transformed to a Feature Dataset. ...