Spatial data processing framework that brings advanced analysis capabilities to QGIS.

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48 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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28 views

Generate equal sized polygons along a line with PyQGIS [duplicate]

One month ago I asked a question about how to generate equal sized polygons along a line in QGIS, which seems to be also interesting to a bunch of people aside from me (20 upvotes and more than 400 ...
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0answers
14 views

Customize QGIS Leaflet webpage [closed]

I created a webpage QGIS map using the Leaflet plugins, how to customize , put mouse over, then features will zoom automatically while you mouse on click on the map features, and also automatically ...
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1answer
73 views

PyQGIS couldn't import processing with standalone script

I have read post on that problem (How can I access `processing` with Python?). The problem is even with a sys.path.append it couldn't import processing. It's very frustrated. Here the code I used: ...
2
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1answer
59 views

QGIS processing toolbox: fieldcalculator - update only selected features is not possible

I am working on a model where I need some calculations on only some selected features. In the normal fieldcalculator you can check 'only update ... selected features'. When using the fieldcalculator ...
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1answer
33 views

Processing time/speed for Mosaic to New Raster

I have a question on speeding up “Mosaic to New Raster” or finding an alternative. After completing a suitability analysis we are trying to define movement corridors. We used a modified CircuitScape ...
3
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1answer
65 views

Get results from using GRASS algorithms with the QGIS processing tool

I am trying to write a plugin in QGIS that uses at some point a GRASS algorithm : "v.split.length", accessible by using the processing class, and here is how I am using it : ...
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1answer
64 views

QGIS - updating Processing plugin

A recent convert to QGIS, I have versions 2.8.5 and 2.12.2 installed on my PC. The plugin Manager tells me I have v2,10.3 of the Processing plugin installed in the plugin folder of my local drive and ...
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1answer
26 views

How to assign a value for Slope of Different percent?

I have slope percent varying form 0 to 25 percent. Now I want to give a value for each slope percent. For example, if my slope percent is 2 % , I want to assign a value of 10. As a matter of fact, ...
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1answer
57 views

SAGA tools in QGIS only allow save as .sdat file?

I'm just beginning to learn how to use SAGA 2.1.2 tools within QGIS 2.12.1 on a Windows 7 64 bit computer by working through exercises in Mastering QGIS by Menke et al. ...
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32 views

Raster calculators in SAGA return incorrect results

Here's a sample of my dataset (one cell) with 28 different raster values, representing 28 individual Float32 rasters with identical parameters. 0.0000264434, 0.0049953502, 0.0007529828, ...
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33 views

C/C++ function to return minimum set of points required to represent a geometric shape

I am looking for a method from Grass, GEOS, or similar that will delete those points in a geometry which do not affect its shape. Example 1 +----+----+ p0 p1 p2 p1 can be deleted without ...
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1answer
46 views

Conditional statement in gdal_calc with result as float, not boolean

Many examples on gis.se that refer to gdal_calc give a boolean example. example 1 example 2 If I need to calculate a conditional statement on a float: If Raster_Value >= 1024, then 1024; else ...
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1answer
57 views

Using each feature of vector layer as clip mask over separate point layer, storing results in either a Python list or in-memory scratch layer

I have a point layer (representing cities), and a set of vector layers whose features are hundreds of concentric discs, each of which I'd like to use as a clipping layer to select only the cities that ...
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4answers
545 views

Generating equal sized polygons along line with PyQGIS?

I would like to create polygons along a line to use them for AtlasCreator in a next step. ArcMap has a tool called Strip Map Index Features. With this tool I can choose the height and width of my ...
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0answers
40 views

heat map plugin from QGIS python console

I am trying to use the heat map plugin from the processing console. On the QGIS documentation it says the plugin uses Kernel Density Estimation. I have used the saga Kernel Density Estimation but do ...
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2answers
252 views

How to make GRASS 7 addon available in QGIS 2.12?

I stumbled across the GRASS-Tool i.segment but could not find it in my QGIS processing toolbox. I found out that it is an addon for GRASS 7 that I already installed in GRASS 7 standalone. How can I ...
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2answers
73 views

Grass GIS: Number of CPU cores to use

E.g. in SAGA GIS it is possible to set with one click the number of CPU cores to use during processing. Is this also possible in Grass GIS?
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1answer
45 views

Writing a QGIS Processing Provider

Due to limitations in the processing script framework (for example, inability to specify an optional field) I'm thinking of writing a Provider. I found the example ExampleAlgorithmProvider but no ...
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1answer
93 views

Has the “Warp (Reproject)” tool changed in QGIS 2.12?

I am writing a QGis plugin, for QGis 2.10, which imports processing 2.10.3, that needs: testproc = processing.runalg('gdalogr:warpreproject', thisName, # input ...
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0answers
35 views

Has “add polygon attributes to points” been removed from QGIS?

I've been using "add polygon attributes to points" in qgis for a while, but hadn't needed it for a while (thanks to Underdark for this); in 2.13.0 master on ubuntu it seems to be missing from the ...
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1answer
86 views

Proper Use of QGIS tool: “Frequency analysis”

Trying to use the "Frequency analysis" tool in a script but getting errors. The Online documentations for this tool: processing.runalg('qgis:frequencyanalysis', input, fields, output) My Script: ...
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1answer
89 views

Create a temporary intermediate layer in a processing script

My algorithm needs a temporary layer in a QGIS processing script. I can use regular pyqgis api to create a temporary layer but want to know if there is a preferred and processing-specific way of doing ...
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1answer
90 views

How to run Refactor Fields algorithm in Python console?

I noticed that the Processing algorithm, Refactor Fields has a fields mapping parameter. I don't think I've come across this and definitely not used it before from the Python Console. It provides an ...
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1answer
63 views

Error in converting SpatialPolygonsDataFrame to Data Frame, R Script in QGIS

I am trying to convert a SpatialPolygonsDataFrame layer to a DataFrame to create plots using ggplot2 in an R Script within QGIS. I've used spatial join to append averages of BioClim mean temperature ...
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1answer
61 views

Use “facet_wrap” in ggplot2 with QGIS?

I'm using QGIS 2.6.1 and R version 3.2.2. I'm struggling to get the syntax on a R Script for creating plots via QGIS processing to work. My understanding is that R syntax in QGIS Processing is ...
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1answer
55 views

Using processing.runalg in python script

I'm trying to run the following python script: from qgis.core import * import sys import os import qgis.utils from qgis.analysis import * app = QgsApplication([],True,"") # supply path to where is ...
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1answer
101 views

Assign shortcut to a script?

Is it possible to assign a keyboard shortcut to a (custom or not...) script of the Processing Toolbox in QGIS? Haven't found any information about it...
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1answer
59 views

Is it possible to inject a value into an algorithm text setting in QGIS Processing Model?

I have a SAGA Raster Calculator algorithm inside a model that I'm building. For the formula, I'm using the function (g1>20)*1 to give me a binary raster output. This categorises pixels to ...
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1answer
73 views

Automatically detect the polygons(Buildings) In QGIS

Am trying to instal BREC plugin in QGIS 2.4 and 1.8 for the purpose of automatically detect the polygons(Buildings) from raster(TIF) file but i can't find that plugin, its not available in plugin ...
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29 views

'NoneType' object has no attribute 'getFeatures' message when using Batch processing clip in qgis

When trying to clip with batch processing in qgis 2.10.1-Pisa I got the error message attached as a screenshot. Any suggestions for resolving it?
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1answer
115 views

QGIS 2.10.1. GRASS Algorithm Processing

While selecting the GRASS algorithms 'Processing algorithm: v.to.points - Create points along input lines' The error message came up: The specified GRASS GIS 7 folder does not contain a valid ...
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1answer
168 views

QGIS 2.10.1 GRASS Processing algorithms not working

I just did a fresh install of QGIS 2.10.1 from the qgis repos (Ubuntu 14.04). I also have grass70 installed (through ubuntugis-unstable). I can see the GRASS7 commands in the processing toolbox ...
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24 views

Fill tool freezes QGIS

I am trying to figure out a way to create a stream order file with the Horton method, however seeing as Arcmap only does either Strahler or Shreve, this isn't ideal. I opted to try QGIS, however it ...
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0answers
30 views

Clear QGIS plot results window

How do you simply clear old plots from the plots result window in QGIS? Is there a line of R code that you'd need to run to do so, or is there a means of doing so through the GUI?
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1answer
58 views

qgis-processing: how to specify optional outputs?

Suppose a script has a variable number of outputs, which may or may not be produced depending on settings: ##Input_layer=vector ##Output_1=output vector ##Produce_output_2=boolean ##Output_2=output ...
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25 views

Processing Tools Help Documentation for QGIS? [duplicate]

I'm used to ArcGIS but am attracted to QGIS for its open source (free) nature. At present I'm trying to use native QGIS processing tools and also script my own algorithms (was used to geoprocessing ...
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1answer
120 views

Create true color image from Sentinel-1 data

Is it possible to create or extract a true color (RGB) image from Sentinal-1 satellite data? Like with Landsat8 data described in this article ...
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0answers
36 views

qgis-processing: possible to specify variable number of output layers?

Qgis-processing advises that output layers are specified with syntax such as ##foo=output vector The manual advises against manually loading output layers (in your script code) as QGIS will do this ...
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1answer
39 views

How to see the 'example provider' in processing toolbox of QGIS?

I would like to create my own provider with the processing toolbox. I see the example provider in my folder C:\QgisWien\bin...\algs\ExampleProvider. It seems to be a good start but unfortunately, I ...
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1answer
51 views

Zonal Statistics doesn't work after updating processing (2.10.2)

After updating the processing tool zonal statistics doesn't work. in method 'SpatialReference_ImportFromProj4', argument 2 of type 'char * Could someone else try if it's a bug or just an issue ...
2
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1answer
69 views

QGIS: can't run processing.algrun() in external Python application

I am trying to create an external Python application. I want to run this as a stand alone program in command line. I am trying to not use the QGIS console. A first step is to clip a point shapefile ...
2
votes
1answer
55 views

How to add my plugin to Processing?

I made a new plugin for QGIS and I want to include it to the Processing toolbar. I can't find a good hint on how to do it cleanly (applying answer of this question on my algorithms seems dirty). So, ...
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1answer
52 views

QGIS Processing Plugin Not Loading “RuntimeError: maximum recursion depth exceeded in cmp”

I am having serious issues with my QGIS program regarding the Processing Plugin. Upon start-up and if I turn on the plugin within the program. I have uninstalled and reinstalled the program. Have ...
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1answer
108 views

Python script to copy first row of certain attributes and paste in the newly digitised rows the copied features

Starting from this question, I need a script to be insterted in the processing graphical modeler that can copy some attributes from the first digitised row in all the newly digitised lines of a ...
2
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1answer
54 views

Processing modeler Output Order

I have a model running on the processing framework it produces a serie of vector layers as output(alt-0, alt-1, alt-2, alt-3, and so on). I have prepared the model keeping the order of these ...
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1answer
44 views

QGIS Processing Input CRS from Input Layer

I'm creating a Processing algorithm that requires the user to input several parameters including an input layer and an output CRS. At present, the tool defaults to SRID 4326. I'd like for the CRS ...
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31 views

is the “configuration dialog” = “Processing” > “Options”

Is the the "configuration dialog" referenced to in help "Processing" > "Options" Note: The 'help' I am referring to is the online Documentation QGIS 2.2 » QGIS User Guide » QGIS processing framework ...
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41 views

Custom QGIS Processing Tool Fails to Copy Features

I'm creating a custom QGIS Processing plugin. I've created a tool that is basically supposed to copy features from an input PostGIS layer to a new PostGIS layer. My routine runs without errors and ...
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168 views

Merge raster layers error

Is there an issue with the SAGA-tool "Mosaicking rasters"? I tried it with different rasters. In Sage itself it works fine. Algorithmus Mosaick raster layers startet... io_gdal 0 -TRANSFORM ...