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

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Syntax error in parameter formula of field calculator funtion

I'm using a QGIS 2.8.1 in windows. Have some doubts with syntax when use string in python console. I want to use the field calculator funtion like: processing.runalg('qgis:fieldcalculator', input, ...
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1answer
223 views

Calculate tree cover over certain area from raster data

Last year Hansen et al. published Global Forest Change map as set of raster data available in TIFF format. Basically those are 30-meters resolution satellite images with pixel values ranging from 0 ...
3
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1answer
295 views

Import error when utilizing QGIS's Python Init function

Based on the answer to Referencing Qt UIs external to plugin with python. I'm trying to utilize the "Layer Properties / Fields / Python Init function" to execute a file (test_file.py) that is located ...
4
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2answers
57 views

performance problem with PyQGIS: manipulating attributes

I have selected a vector layer with attributes slope and area. I want to combine all the features with slope 0 to 5, 5 to 10, ... , 85 to 90. The original features are to be discarded, and new ...
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2answers
78 views

intersecting two shapefiles from Python or command line

I'm new to working with geo data and trying to address a similar question to the one posted here. Using command line and/or shapely/fiona, in the most efficient and elegant way. I created two ...
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2answers
872 views

Scriptable alternative to ArcScan (particularly vectorising lines within tolerances)?

Sadly the answer to Can you access ArcScan from a python script? suggests that it is not possible to script ArcScan from within a python script. Therefore, does anyone know of any alternatives to ...
3
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1answer
278 views

How to clip a Oracle query layer directly in a Python script?

I have a query layer directly running from ORACLE database in a MXD. I want to clip this layer with a layer being created in another MXD in a Python based tool. My question is to do this clip ...
2
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1answer
107 views

How to detect corner of shapefile in python [closed]

Is there any way to detect corner of each shapefile in python !? (not BBox) Or somehow to detect the edges? I want to detect each shapefile vertices to calculate the differences in latitude for my ...
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2answers
971 views

Is there a way to call the clip function in pyQGIS from the python console?

Is there a way to call the clip function in QQGIS from the python console? It is found under geoprocessing tools in the vector menu.
3
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0answers
67 views

Select shape file by their coordinates behavior [closed]

I want to filter shapefiles by their latitude behaviour: If the latitudes of edges A and B are constantly decreasing or increasing then this class marked as correct, otherwise are incorrect. For ...
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1answer
241 views

Orthographic projection in Python Basemap

I'm trying to plot a GeoTIFF in Python using Basemap. I can do so correctly with cyl projection like this: m = Basemap(projection='cyl', llcrnrlat=LL[1], urcrnrlat=UR[1], ...
5
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3answers
638 views

How to define layer's CRS and avoid the CRS dialog in PyQGIS?

There is an existing Shapefile, which I want to add. At the moment my code looks like: self.iface.addVectorLayer(self.shpFilePath, "Track", "ogr") It works fine, but i want to define the crs ...
2
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0answers
38 views

Setting extent with python in QGIS in new project

Situation: I am trying to write a simple python script for QGIS. The script aims to load one layer, zoom to given coordinates, and 'place a pin' there. The coordinates will change every time I run the ...
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1answer
37 views

PythEveryone in ArcGIS virtual campus module: Runtime error + namerror

I'm working on the python for everyone lab in Esri's Virtual campus. I'm running into an issue that I can't seem to solve, I've already done some outside research hence posting here! The issue: 4th ...
7
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1answer
130 views

ArcGIS Pro and ArcGIS Desktop on same machine

I'm just trying out ArcGIS Pro for the first time and I had to change my PYTHONPATH to python34 ArcGIS Pro is now working without crashing every time I open the Analysis tab... However now when I try ...
3
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1answer
77 views

How can I use GDAL Merge with multiple files in one folder in python 2.7?

I have multiple files in one folder which are called, for example: 049.h11v11.hdf, 049.h11v12.hadf, 049.h11v13.hdf, 065.h11v11.hdf, 065.h12v12.hdf, and so on. The first 3 numbers are the julian day of ...
3
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2answers
306 views

GDAL with GEOS support, pandas and VTK using python on Windows?

So far I have been using OSGeo4W shell (or OSGEO install) as really convenient way to use python together with additional packages, namely gdal, shapely, numpy, scipy and matplotlib. I was happy till ...
2
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1answer
98 views

Huge file size after averaging two rasters

After I average two raster files (singleband gray, initial size ~700MB each) through QgsRasterCalculator() with formula "Raster1@1/2 + Raster2@1/2" the size of the resulting file is 2.9GB. Is there ...
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1answer
26 views

How to determine the appropriate size of a 3 dimesional raster block/chunk

I am processing large MODIS time series (12 years) dataset with an array dimension of 4800 x 4800 with a data type of Int16-Sixteen bit signed integer. I want to build a 3 dimensional array ...
2
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1answer
40 views

Working Windows Standalone .EXE From QGIS Python Script Using PyInstaller?

Has anyone been able to create a working standalone Windows .EXE file from a QGIS Python Script Using PyInstaller?
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1answer
49 views

ArcGIS REST API: using /addItem with secure service

Using the code below I am adding 100's of Map Services to a portal instance. The script successfully runs and adds them however the services are secure so I would like portal to store the username ...
3
votes
1answer
82 views

How can I install pyproj into arcpy?

I am trying to install pyproj. I downloaded the zip folder on this page pyproj. Then I copied it to C:\Python27\ArcGIS10.3\Lib. However, when I try to import the module, I get the message ...
4
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3answers
510 views

3d vector and geometry operations in open-source GIS

There is some really good open-source software available to work with 2D vectors. For example QGIS has operations like buffer / clip / dissolve / select by location / join attributes by location... ...
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1answer
166 views

How to set up pycsw on xampp (win7)?

I'm trying to setting up pycsw on xampp. In the pycsw's default.cfg I've the following configuration: [server] home=C:\Users\masa\xampp-201405\htdocs\pycsw url=http://localhost:8000/pycsw/csw.py ...
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1answer
29 views

Rasterize vector file using gdal.RasterizeLayer() without losing attribute information in python

Is it possible to rasterize a vector file with gdal.RasterizeLayer(), saving attribute as Raster value ? Like gdal_rasterize can do with : gdal_rasterize -a attribute -ts rasterXsize rasterYsize -l ...
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1answer
181 views

Conditional SQL Query

I've been running a code that searches a desired field in a feature class and performs an specified SQL query based on whether the field is string or double. The variables are just temporary fillers ...
5
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2answers
294 views

What's the most efficient way to load feature attributes into a numpy array?

I am currently working on an add-on that relies on the user choosing fields of tables (that can be from shapefiles, csv or dbf) that are open in QGIS and then making computations with such data. ...
4
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2answers
1k views

Can we create a temporary in-memory geodatabase using python?

I have been using in-memory workspace for creating temporary features, but I was wondering if we could create a temporary in-memory geodatabase (using python) and then use it for importing other ...
2
votes
1answer
247 views

Refreshing display for newly added labels with ArcObjects from Python?

I've added a shapefile to an MXD and Edited the symbolization of it with ArcObjects. Now I'm trying to edit the labeling with ArcObjects. I've successfully been able to edit the default class in the ...
19
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6answers
3k views

How to make a GIS inventory?

My office will be seeing a big change in its GIS section. This section has been operational since the 1980's and has a huge collection of GIS data (i.e., shapefiles, raster files, data, etc) but never ...
4
votes
3answers
838 views

Programmatically creating exports from PostGIS database into different file formats (e.g. shapefile, dxf, dgn,…)?

Is there a kind of wrapper/library written in python which would enable me to programatically create exports from postgis database into different file formats (most common being, shapefile, dxf, ...
3
votes
2answers
58 views

merge dbf files - without using arcpy?

I have ~7,000 2 line dbf files (zonal stats output) that I would like merged into one table, all the same format. I have used the arcpy merge tool, as seen below. #merge tables together ...
7
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0answers
142 views

gdalwarp producing empty rasters when called from python script, but not via command line

I'm trying to aggregate some raster data (all .tif) up to a coarser resolution (from .05 degree to .25 degree) using gdalwarp in python, but the command is not working. Instead of getting an output ...
0
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1answer
485 views

Polygon Neighbors Analysis script (ArcPy 10.1) producing erroneous results?

I'm struggling with a python script that is supposed to calculate a field for a polygon feature class. The calculation is of the average of a field value (P_TOT_DEV) for each of a given polygon's ...
2
votes
1answer
43 views

Why is QgsFeatureIterator returning bad data?

This is a spin-off of another question I asked previously, but it has grown in scope and deserves its own thread. While iterating over a vector layer (shapefile) I included the following ...
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2answers
183 views

working with geojson and vincent on python

I want to import a geojson file into python so I can map it with a visualization package vincent and merge with other data in a pandas data frame. To be specific, the said geojson file is: ...
3
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1answer
85 views

Convert KML to GeoJSON with ogr2ogr and remove KML special attributes

I'm trying to convert KML to GeoJSON (or some other formats) using ogr2ogr (look at this question). It's all working fine, except of one problem: I'm always receiving these metadata attributes with ...
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2answers
95 views

Calculate the distance between two coordinates (WGS84) in ETRS89

I have an Excel-file with coordinates (WGS84). From these coordinates I create a line (shp) and transform it (ETRS89). After the transformation I calculate the distance from point to point. I do this ...
4
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1answer
389 views

How do I link OGR with spatialite?

Problem & Evidence: I'm trying to create a spatialite file with the code snippet below. However the outDataSource object gets assigned NoneType and all subsequent (unshown) code fails. I'm ...
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0answers
34 views

Arcpy 64 bit, or multiple Python installs? [duplicate]

I am new to Python, and am trying to write a script that would upload a geodatabase to AGOL at a scheduled interval. However, the 32 bit distribution of Python cannot handle the file size (over 1 MB), ...
1
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1answer
50 views

QGIS Processing Script will not Validate

I am writing a script for QGIS that will identify the perimeter of only external facing walls. The script is probably a little long to post directly into this post, but it is accessible here. The ...
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vote
2answers
32 views

Error Installing GDAL python package on a MAC

I'm trying to install the [GDAL python package][1] on a Mac (OSX Yosemite) with python 2.7.9 and GDAL 1.11.3. When I try $ sudo easy_install GDAL I get a number of errors ending with: error: Setup ...
4
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0answers
34 views

How to unproject a UTM ESRI Shapefile over WGS84 extent boundaries

Background: I am working on a collaborative project in Python that uses GDAL/OGR to work with rasters and vectors. There is one function that attempts to project one ESRI Shapefile's coordinate ...
2
votes
1answer
45 views

IPython plugin not loading in QGIS 2.12

I am trying to run the IPython console plugin in QGIS 2.12 After installing the plugin there is this error: You need to install IPython 3.1.0 (and then restart QGIS) before running this ...
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2answers
121 views

GDAL Translate error

I am trying to translate a .tif raster to an xyz one in Python The code is this: import sys from osgeo import gdal gdal.AllRegister() driver = gdal.GetDriverByName('Local Disk') dataset = ...
1
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1answer
31 views

rendering a single band raster - new maxvalue

I have a downloaded raster file, singlebandgray, and want to redefine it's maximum value to a higher integer value. Via the QGIS desktop it works smoothly by hand via the Properties. Via Python I was ...
4
votes
1answer
1k views

How to create mask bands in GDAL and Python?

I have small program in Python that uses gdal and numpy to perform a logarithmic scale of some data into the RGB 0-255 range. Now this input data has a nodata value set to mask the valid values, and ...
0
votes
1answer
417 views

Error in Select Numeric type column in pyodbc with ArcCatalog

I created a python script that uses "pyodbc" plugin to connect a SQL Server database and write out data. It was imported in an ArcGIS 10.1 tool and run from there. try: arcpy.AddMessage('FLAG 0') ...
2
votes
1answer
39 views

Actions undertaken in QGIS somewhere stored as Python code in a history file?

For practioners that are not willing to study all the methods for each class, it would be helpful if every action that was made within the QGIS interface can be looked up afterwards in a history file ...
1
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1answer
199 views

gdal_proximity distance to meters

I followed the answer given in this topic for searching the distance to the nearest coastline given a lat/lon coordinate. The distance output obtained is in degree (I think) but I need the distance ...