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

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59 views

Regridding vector values

I'm trying to regrid and interpolate vector values from WAM model output. I got WAM model netCDF output in rotated grid, I need to interpolate it to another grid which is some variant of LAEA ...
2
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169 views

Combining custom QWidgets with ui file generated from QGIS plugin builder?

I am having a hard time figuring out how I can include several QWidgets (created in individual scripts) into the QT Designer ui file generated from a QGIS plugin builder. These are custom widgets I ...
2
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0answers
56 views

Finding start and end junctions of road from coordinate on road

I have a list of co-ordinates where traffic counts were carried out. I wish to associate these traffic counts to the link they are selected with. For that link I want to know the location of its two ...
2
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0answers
138 views

Is it possible to call FME transformers (or workbenches) from my python script?

I have a script mostly using arcpy, and in the middle of this script I convert a load of polylines to polygons: arcpy.ET_GPPolylineToPolygon("Contours_L_1m.shp", "Contours_G_1m.shp", "FALSE") This ...
2
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0answers
67 views

Some layers won't load when running application out of QGIS. “Item has already been added to this scene”?

I'm developing a basic application out of QGIS and am having trouble getting my code to generate all the layers I have set. Currently it only generates two of the four layers: "self.basemap_layer", ...
2
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0answers
56 views

How to display selected features in a map to exporte as PDF

I've already managed to select feature by ID in a layer and zoom to it using pyqgis. The canvas considered this changes but the map that I exported as PDF do not consider this changes, any idea to ...
2
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143 views

ArcMap Label Help - Label from X/Y Coordinate

Edited: This picture might help explain my question. Here I have a point at the line with an X/Y coordinate. It also has a leader line to it. This leader line has an X2/Y2 coordinate. Both of ...
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105 views

Multiprocessing in python qgis?

When i try to do mutliprocessing in python Qgis it doesn't work from multiprocessing import Process,Lock import multiprocessing def name1(l,i): print i if __name__=='__main__': lock=Lock() ...
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176 views

Can we create buffer analysis using python in qgis?

Can we create a buffer of distance 0.004 using python in qgis. I tried this link, but it isn't working for python in qgis 2.10.1-Pisa. The above is the diagram of buffer I am asking. It's located ...
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279 views

How to integrate QT User Interface with QGIS Python Plugin?

I created a very simple python program using GDAL to calculate the summary and reduction between two raster value like this : import os from osgeo import ogr, gdal from gdalconst import * ...
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68 views

Creating new empty vector layer that has same set of atributes as another layer and then copying subset of features into it

I am new to both Python and QGIS. Here's a sample of my code: unique = layer.uniqueValues(index) attributes = layer..dataProvider().fields().toList() assistant_layer = QgsVectorLayer("Point", ...
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66 views

Multiple layer intersection

I am trying to find a way with qgis/python to get the intersection area of more than 2 layers. All the tools in Qgis take just the 2 input layers. ='( For example in the image below, I have 4 ...
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50 views

Can't import liblas into OSGeo4w Python on Windows machine

I installed the 32-bit version of OSGeo4w with the liblas-python packages on my Windows machine. When I try to import liblas into python, I get an error that no 'liblas' module can be found, even ...
2
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0answers
76 views

Cul-de-sac (curve) turns generation in flow for parallel lines using ArcGIS for Desktop?

I'm using ArcMap 10.2 and I need to generate a parallel lines within the polygon and connect them one to other with the curve, with the proper radius and return radius (the same as cul-de-sac tool ...
2
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0answers
68 views

QGIS QgsLayerTreeGroup signal “currentLayerChanged”?

In a pyqgis context, I use the "currentLayerChanged(QgsMapLayer *)" signal of the QgisInterface class to do something when the current layer is changed, but I need now to do the same when I select a ...
2
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130 views

Using Python to iterate through directory to create event layer and perform kernel Density for each file?

I am new to Python for ArcGIS, but have been using ArcGIS a while. I have a large directory of tables with point data. For each file of each folder I want to create a kernel density layer. I have ...
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0answers
115 views

Spatial join with multiple intersecting features

I have a polygon dataset representing pavement areas broken up by year of construction and a roads centerline dataset that contains values for remaining service life (RSL). I want to spatially join ...
2
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68 views

Create a sript for “point sampling tool” of QGIS

Is there any way to create a python script to the "point sampling tool" plugin from QGIS? I have a very large number of Netcdf files which I want extrat the values from pixels to a irregular points ...
2
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84 views

QGIS not interacting with iface from python class

So I'm working on something where i need to use threads from python console of QGIS. The following line of code adds layer successfully iface.addVectorLayer("D:\ArcGIS Misc\Atlas\points.shp", ...
2
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135 views

How to create line segments between pairs of pixels in a raster?

I want to draw several lines between pixels (please see the image below) according to some criteria : First Criterion: The distance between 2 pixels is less than 2000m and greater than 500m ...
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78 views

How to clip or erase a csv file with a non-rectangular shapefile?

I can clip a csv file with a ogr2ogr having 4 extents of a rectangular polygon. Is it possible to clip a csv file with a non rectangular shapefile?
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111 views

GDAL equivalent to ArcGIS Union?

I have a single shapefile full of overlapping polygons. The ArcGIS Union tool will generate individual, non-overlapping polygons with that geometry. Is there a way to do this with GDAL/OGR or another ...
2
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0answers
578 views

open-source code for the map matching algorithm

For map matching of the GPS data to the network data, there is a algorithm from Schussler, N. & Axhausen, K. (2009a). Is this algorithm released under open-source license ? Where can I find this ...
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189 views

How to run Focal Stats on specific values in python

I'm a beginning programmer and am new to the site but it has helped me quite a bit so thank you! I'm trying to recreate a raster calculator operation using python scripts but am having a hard time ...
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196 views

How to access Landsat bucket from Amazon?

I tried to access amazon Landsat S3 bucket with the following python code import boto import boto.s3.connection from boto.s3.connection import S3Connection access_key = <userid> secret_key = ...
2
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58 views

Error inserting new column in ArcSDE table (ERROR 999999)

I am using a python script to populate a table with values I get from rasters files. I use arcpy.AddField_management to add a new column and arcpy.CalculateField_management to insert the values for ...
2
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50 views

Query out a specific date regardless of the time, using python

Problem: I have a feature class with an attribute table with a field called Edited_Date and its data in the field is as follows: 4/8/2015 10:00:00 PM. I want to select all records that are Edited_Date ...
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366 views

DBSCAN gives “AttributeError: NoneType has no attribute issparse”

I am running a Python script invoking the DBSCAN tool to cluster feature points. When I open ArcMap, load the feature layer, and run the script, it works the way I expect it to. But if I run it ...
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48 views

GDAL merge; Why add 0.1?

In the implementation of gdal_merge: https://svn.osgeo.org/gdal/trunk/gdal/swig/python/scripts/gdal_merge.py a value of 0.1 is added to the conversion from geo-referenced coordinates to pixel ...
2
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0answers
100 views

Not able to get the PostGIS Layer Viewer running in pgAdmin or command line

I've installed PostGIS Layer Viewer as a plugin for pgAdmin. I've downloaded postgis_viewer.py from the official repository on GitHub! and followed the install instructions described on Web site!. ...
2
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0answers
643 views

Running Python outside of QGIS - (ImportError: No module named qgis.core)

I'm trying to run simple scripts on QGIS from outside the QGIS environment - as here How to run a simple python script for QGIS from outside (e.g. Sublime Text)? My code: import sys ...
2
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419 views

Speed up row-wise point in polygon with Geopandas

I have a geopandas GeoDataframe which contains some attributes and a geometry column which is filled with shapely Point(lon, lat) objects. Moreover, there is a GeoSeries which is equally indexed as ...
2
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0answers
100 views

Using ST_AsText() without session object

I am storing gps locations as feature in a restfull api. The locations are linked by foreign key to "place" objects in a flask/sqlalchemy/geoalchemy framework. I would like to print a user readable ...
2
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0answers
37 views

QGIS Python Script for RoadGraph plugin

I am looking to create a Python script that will take X,Y coordinates from one field in an attribute table, compare them to another set of X,Y coordinates in a different field, and populate a field ...
2
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0answers
116 views

How to Bulk “Add Selected” Attributes to a Relationship Class ~ 40000 Records

I have 2 Feature Classes (FC's) and 1 Relationship class. FC1 and FC2 share a common field with almost 40,000 matching records. For each matching record (i.e. when the matching records from FC1 ...
2
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0answers
61 views

Updating Cursor to Include Newly Created Features

I am using ArcMap 10.1 and python to create cursor that starts at the one and only row of a polyline shapefile, some code runs to create a new feature based on the position of the exisiting feature, ...
2
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0answers
143 views

Using processing using other output (result from another algorithm) as input

I have a problem. I am developing a standalone app in python and I need to use processing algorithms. I was able to use one algorithm without erros but I need to run other processing algorithm which ...
2
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0answers
68 views

How to change values in a raster file at particular positions?

I have a collection of coordinates which comes from a QGSGeometry object. The shape is a polygon. example: qgsGeometry [[(75.2172,17.6566), (75.8499,17.9613), (75.5218,17.2113), (75.2172,17.4574), ...
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0answers
212 views

Geoprocessing Service on ArcGIS Server to Export File

ArcGIS Server / Geoprocessing Question I have a geoprocessing service that will perform a selection on a layer based on a provided expression. I would like to output the result as a csv file (or ...
2
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0answers
137 views

Error when running Python script to replaceDataSource of multiple layers in multiple mxd's

I looked on all of your sites and did not find a solution to my problem. Almost all of our data has been copied to an SDE and now most of the layers in all of the mxd's need to be redirected to the ...
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0answers
24 views

Help getting a Mathematical Representation within a Layer's Attribute Table

I'v been playing around with Vector Coding and was wondering if there was any Plugins out there that might let me represent Vectors within a layer as it's Mathematic attributes in the Layer's ...
2
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0answers
84 views

Help with Python/GDAL documentation

The instructions from the url http://gdal.org/gdal_tutorial.html give the following example: dataset = gdal.Open( filename, GA_ReadOnly) with the following description: It's interpretation is ...
2
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0answers
462 views

Iteratively exporting from Table to .txt in Model Builder (ArcMap) not appending correctly

I am solving a location-allocation type of problem where I use a loop to go through several specifications of the problem. The model runs fine, and produces the vizualization outputs just as expected. ...
2
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0answers
76 views

Programmatically Harvest and Disapprove Metadata - GeoPortal Server

Is it possible to synchronize an existing metadata catalog in esri's GeoPortal Server? I have access to the server, and have a script to add an XML file to our web accessible folder. After this script ...
2
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0answers
39 views

QGIS Python install question

Apologies for the 101 question; however, in trying to ramp up on python/QGIS I've seen mentioned that python.exe is the key executable in a python install. I have both Python 2.6 and 2.7 installed on ...
2
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0answers
138 views

multiprocessing and the ArcGIS in_memory workspace

I am trying a script that makes use of multiprocessing and a number of tools within arcpy. The script works only if I write all input, intermediate, and output from child multiprocessing executions to ...
2
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0answers
219 views

How to open a second window in QGIS plugin from a button inside the main window

If I already created a qgis plugin, and i need to create a button inside that plugin that opens a new window, how is that possible? Qt creator won't add a slot unless there are a header file. I looked ...
2
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0answers
250 views

How to convert a raster file (*.tif) into a composite geodataset by using Python in ArcGIS 10.2.1

I created geotiff rasters (approximately 6000 rasters) in .tif format by using Matlab Mapping Toolbox. When I examined the properties of the data, I realised that it is 64 bit double type. I need to ...
2
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0answers
287 views

Splitting Line.shp at Point.shp with Python/ogr

I'm trying to modify some ESRI Shapefiles using Python with gdal/ogr module. What I want to do is quite simple, but I didn't find any solution by now. I have two shapefiles: (1) Lines.shp and (2) ...
2
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0answers
387 views

Matplotlib error when installing Molusce or lifemapper in QGIS Brighton

I am installing plugins via the QGIS desktop internal interface, and have had twice now messages associated with matplotlib. The first error was for something called lifemapper and now for MOLUSCE. ...