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

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10
votes
2answers
632 views

How to implement MultiValue Parameter with Multiple Columns?

This might be a simple question, but I haven't been able to find a straightforward answer. I'm working on an ArcGIS (9.3) Python script. One of the inputs is a list of features. For each feature, I ...
6
votes
5answers
1k views

Python, shapely library: is it possible to do an affine operation on shape polygon?

I am trying to create a rotated rectangle in lat/lon coordinates. Basically, I have the coordinates of the center and rotation angle around the center. Is it possible to do using, shapely or gdal, ...
2
votes
2answers
84 views

Find the first occurrence of any letter in an alphanumeric string [on hold]

Working in arcgis desktop 10.2, I use python scripts to split some strings, found in an attribute table. Most of them were quite easy to split, but here is one that i could't manage to break. ...
1
vote
1answer
20 views

errors after installing 64 bit background geoprocessing on ArcGIS desktop 10.2.2

I installed 64 bit background geoprocessing on my ArcGIS 10.2.2 and then changed my pythonpath to "C:\Python27\ArcGISx6410.2" so that my code can benefit from the 64bit. then I had to install a 64b ...
0
votes
1answer
277 views

visualize bounding box to a polygon

I try to make plugin in QGIS that compare 2 bounding box data, ex: (-32.61442167739459, -32.017601026186576, 13.015663782506067, 13.428145228091406) and (-38.6102467739459, -38.017601026186576, ...
4
votes
2answers
424 views

How to upload a shapefile to geoserver using cURL?

I need to automatically (using python) upload a shapefile into my geoserver. I'm trying to do as described in here but i'm getting this error: java.io.IOException: Wrong magic number, expected 9994, ...
1
vote
1answer
51 views

How to perform If Statement in Field Calculator of ArcGIS for Desktop? (Python or VB)

I've one field "MAXSPEED". I want a Field Calculation that will calculate an additional field ("noise"): If MAXSPEED > 40 then the term: (73.5 + Log ( 25 ) * ( [MAXSPEED] / 50)) should be used to ...
0
votes
0answers
19 views

contour making issue

I have include vector layer using postgis database with filter(data between two dates) it work fine but after adding when I trying to make a contour from it I get error Exception encountered: ...
0
votes
0answers
14 views

python code doesn't preserve original range of values from my raster colormap template

I'm working towards an animation or movie of some distributed model output so I need to use a batch process for several hundred rasters that applies a consistent colormap and value range, however the ...
3
votes
1answer
497 views

Multiprocessing issues with ArcPy

I am using ArcGIS 'watershed' routine in a script which makes use of multiprocessing. This works fine, but during execution I get the message: Unable to remove directory. Possible causes: 1- Not ...
3
votes
1answer
32 views

Python output for batch “FeatureToRaster” in ArcPy

I am trying to batch process the conversion of shapefiles to rasters. I am stuck on how to specify the name for each output raster file. Part of the trick is that my input shapefiles are the names of ...
3
votes
0answers
14 views

Send signal when attributes modified - QGIS 2.6

For a QGIS 2.6 python plugin, I am trying to send a signal when an attribute value is changed (values for an existing feature are updated or added and the attribute form dialog is accepted). This ...
0
votes
1answer
38 views

problem with adding 64-bit background geoprocessing to ArcGIS 10.2.2

My code written in python language using Arcpy works perfectly with small to average size datasets; however, with a big dataset, the script stops in the middle of execution which most likely is due to ...
1
vote
2answers
73 views

Insert.da.Cursor, Error - Sequence size must match size of row

So I'm working on this script which creates a table within a geodatabase. It then grabs the unique values from a list and attempts to insert them into the table using an Insert Cursor. I get the ...
1
vote
1answer
17 views

Why use QgsFeatureRequest() when iterating?

I am unclear on why one should use QgsFeatureRequest() when iterating over a file’s features. Let’s say I would like to print out all IDs in my currently active dataset. Now, most examples will ...
1
vote
1answer
63 views

How to select and zoom in features from a QGIS Python Plugin

I'm very new to Python. I'm trying to find a way to select and zoom to the features from a QGIS layer. I've created a plugin and built a custom form. I have 3 values from the form which I need to ...
3
votes
1answer
37 views

methods for converting coordinate datum and format in python?

Related to an earlier Q&A of Missing grid shift files for cs2cs.exe? ... what are the various methods to convert coordinate datum and format in python? (Windows Vista, python 3.4) For example, ...
2
votes
1answer
66 views

Run processing toolbox outside QGIS in standalone app

I am developing a standalone app in Python, using QGIS libraries including processing algorithms. I am developing in Linux environment and I put the libraries in a folder. Also I put the processing ...
7
votes
2answers
548 views

How to write scripts that can call on both Arcpy and PyQGIS?

I have spent quite a bit of time looking for a clear answer this topic and have still been unable to really accomplish my goal of accessing PyQGIS in a stand alone script. Parts of answers have been ...
3
votes
1answer
325 views

Configuring spatialite database access for Python 2.6.6

I'm working on a GIS project, and I would like to implement and test some geo-spatial algorithms in Python. For this purpose, I will not only need sqlite, but also spatialite, in order to store and ...
2
votes
1answer
16 views

Python-OGR how update the geometry of a point

I need to change the coordinates (geometry) of some points in a shapefile. I can't find the good method. if ( zone[best_y, best_x] >= ( nb_pixel_area - toler) ) and ( zone[best_y, best_x] <= ( ...
0
votes
0answers
19 views

K-means cluster analysis with initial centers with ArcGIS

I am trying to figure out a way to make a K means cluster analysis using initial centers for the clusters, and only classifying, no iteration, for the features in a feature class. Having a feature ...
1
vote
1answer
51 views

Edit attribute table for shapefiles in folders and subfolders with arcpy?

Continuously to Merge shapefiles in folders and subfolders with arcpy I try to edit attribute table for 20 shapefiles that spread in big a folder and are divided to a lot of sub folders. All ...
0
votes
2answers
102 views

arcpy calculate string field: Any ideas what how to fix this?

I'm trying to store a string value obtained from a loop through a tuple into a field called ROW_1. The code goes like this: for creekclass in listOfClassTuples: (classname, Permanency, ...
1
vote
1answer
22 views

Adding Origin to Geotiff using Python GDAL?

Alright, so I'm getting closer to figuring this out but I'm stuck at one (that I know of) thing... how do I use GDAL to apply a known origin of a GeoTiff to another that has been processed in ...
0
votes
1answer
236 views

Orthographic reprojection with mapnik

I am trying to create a google earth like wep application. My problem is that I can't get to render a full view of the earth. The zoom_all() function generates the following error : RuntimeError: ...
1
vote
0answers
40 views

Create polygons enclosing same number of points on PostGIS

I have a geodatabase on Postgis with points representing customers, what i need is give a number of customers, lets say 100 and it need to generate polygons enclosing 100 clients each one. I only ...
1
vote
2answers
29 views

GeoTiff to ndarray

What is the most elegant way to import a multiband GeoTiff as a ndarray using Python? The most common approach I've seen is as follows: from osgeo import gdal arys = [] ds = gdal.Open('sample.tif', ...
2
votes
0answers
24 views

Efficiently generate Voronoi layers in qgis via Python

The following python commands both appear to function when called in qgis 2.6 to generate Voronoi diagrams: processing.runalg("qgis:voronoipolygons", pointLayer, 1, None) ...
2
votes
0answers
122 views

N Nearest Neighbours efficiently PostGIS/Python

The data is worldwide about a million points, lat/lons, with an id and an importance value (0.0 to 1.0), and it's limited to being on land. Ideally I need to cluster all 1 million points into 100,000 ...
15
votes
3answers
9k views

Listing all feature classes in File Geodatabase, including within feature datasets?

From python how can I build a list of all feature classes in a file geodatabase (*.gdb), including inside feature datasets? The standard example only lists feature classes at the top level of the ...
1
vote
0answers
98 views

How to rotate u and v components of wind in rotated gribs?

I have a grib message of a rotated hirlam product. The grib message states, that the u and v component contained are relative to the rotated grid. How can I unrotate them?
1
vote
0answers
11 views

Ogr Python API: set null values in feature

Im trying to convert OGR geodata from one driver to another, like the command line tool ogr2ogr do, but using the python API. My problem is, that the NULL values in the input data are converted as ...
0
votes
1answer
46 views

Add field to feature class by location

im trying to write a script that allows me to iterate through my map layers, and for each layer, iterate over each feature and add a field that gives the location of the feature using my index layer ...
1
vote
0answers
22 views

Longest Common Subsequence for trajectory matching in Python

Is there any fast implementation of the Longest Common Subsequence algorithm for trajectory matching in Python? Ideally it would work with trajectories of different length in 2d spaces.
1
vote
2answers
126 views

AML routines and python

I´m trying to use some AML files in ArcMap 10, but I have noticed that this option is not available for this version. Does anyone know or tried to "translate" the aml sequences to another language ...
2
votes
2answers
63 views

Can we no longer reference an ArcMap layer to get the spatial reference?

I'm currently using ArcGIS 10.2.1. In previous custom geoprocessing tools, I've used the following code to create a feature class in-memory, and set the spatial reference using an existing layer in ...
1
vote
1answer
31 views

Error using arcpy.da.SearchCursor and MakeFeatureLayer

im trying to write a script that allows me to iterate through my map layers, and for each layer, iterate over each feature and add a field that gives the location of the feature using my index layer ...
5
votes
2answers
525 views

Load and display a layer using PYQGIS

I'm having a go at using pyqgis from within the QGIS python console to load a layer from SQL Server and display it. I feel like I'm part way there but I'm having a real issue getting the layer to ...
6
votes
2answers
266 views

How to load a raster layer at the top of the QGIS ToC?

The following code inserts my new_layer just above the active layer in the QGIS ToC. new_layer = iface.addRasterLayer(...) Instead, I'd like my new_layer to be inserted at the top of the QGIS ToC. ...
1
vote
1answer
573 views

Linux Client for OpenGTS server

I've installed an OpenGTS server and successfully linked it with the GPS2OpenGTS_Pro application for android. The buses I'm tracking offer 3G with a wireless AP, however whenever the bus stops, the ...
0
votes
0answers
13 views

mapserver python mapscript WFS RAW POST data

I installed mapserver-6.2.2 and python mapscript in a Openshift gear (Red Hat cloud). But I can't work with WFS RAW POST data. This is my configure line ./configure --prefix=$OPENSHIFT_DATA_DIR ...
2
votes
2answers
190 views

Issue while running grass from subprocess

I have a map based web application using geodjango. I needed to display the crime hotspots within a selected polygon area. I found that v.kernel is very good for generating heatmaps/hotspots. So in my ...
0
votes
0answers
36 views

Tool to create triangle buffer using Python in ArcGIS Desktop?

I want to make a tool to create triangle buffer by python script in ArcGIS, like circle buffer that we use it in ArcGIS Desktop? I need a tool that allows user to input the length of sides of the ...
2
votes
0answers
42 views

Overwriting layers in a geodatabase maintaining its position in a feature class list

I'm working with ArcGIS 10. I work on ecological habitat mapping. I have some features classes inside a geodatabase which represent years of data on a specific area. Each has a reliability field with ...
1
vote
1answer
25 views

QGIS 2.6 : Programmatically setting key value pairs for ValueMap widget

Using QGIS 2.6 and Python 2.7 on Windows 7, I am trying to programmatically insert key value pairs into a ValueMap widget via a csv file. Issue is that some of the values are properly inserted and ...
1
vote
2answers
63 views

How to add 2 layers in qgis and display them at the same time

I added 2 layers in qgis using python but only one layer is shown on canvas. After clicking (anywhere on the canvas) both layers are displayed. layer = ...
1
vote
4answers
225 views

Python script to open many small images in QGIS

I have access to about 1000 satellite images that covers my country. Each of them is associated to a smaller image that is used for browsing the real deal. I would like to write a script that will ...
0
votes
1answer
181 views

Spatial ETL Tools won't run “AttributeError: 'module' object has no attribute, etc.”

I have a python script that runs 5 Spatial ETL tools that I wish to run as a scheduled task. Each of the tools will run successfully from ArcCatalog and also from the ArcCatalog Command line. If I ...
2
votes
0answers
65 views
+50

filename of current style in QGIS using Python

I get the name of the current style file using layer.styleURI(). Then, I change the style file using layer.loadNamedStyle(different_filename). However, when I call layer.styleURI() again, it returns ...