SAGA (System for Automated Geoscientific Analyses) is a GIS toolbox with many modules that can be used from the GUI, command line or accessed through R,python or directly using C++.

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Topographic Wetness Index

Is there any option to SAGA to calculate the Topographic Wetness Index ? I have a big area and I tried many times with SAGA, the last time I thought the results was ok (before SAGA would crash or give ...
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171 views

SAGA Cluster Analysis for grids projection issue

I am having an issue with the SAGA cluster analysis for grids tool within QGIS 2.4. I am actually taking this as an online class through Del Mar and we are going over supervised and unsupervised ...
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“Select a tool” error Saga: Accumulated cost (isotropic)

I'm trying to run Saga's accumulated cost operation in QGIS on a DEM and set of raster destination points, but keep receiving an "Error: select a tool" in the log after a failed run. There are no ...
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20 views

QGIS: How to create a crosstab using SAGA toolbox cross calssification and tabulation?

I am trying to use Cross classification and tabulation SAGA toolbox. I have a raster DEM file (14 classes) and raster file precipitation (13 classes). I want to do cross-tab - but I don't know how ...
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287 views

Why is SAGA from the Processing Plugin not recognised?

Similar to this post: SAGA algorithms don't work in QGIS 2.8 except the fact that SAGA does not appear at all in the Processing Toolbox: As a check, I used the Python Console with the following ...
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SAGA 2.2.5 Problem Object Based Image Segmentation

Every time I use the Object Based Image Segmentation with Landsat 8 data I get a segmentated image which looks like a spider's web. The image contains no 0 values. Anyone has a idea how to fix this?
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Python script using SAGA and arcpy for converting 'on the fly' LAS point cloud to shapefile?

Summary: I have created a process to import a LAS point cloud, clip it, select the ground points and save the output as an XYZ.txt for clients to use. This uses a python based script (will become a ...
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22 views

How to interpolate (ordinary kriging) large files with QGIS processing

I'm using the Saga ordinary kriging tool as apart of different processing models. The biggest issue I have is the very slow performance. My point shape files have mostly more than 200.00 points (some ...
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739 views

How to create a time series with a NetCDF raster from Ensembles E-OBS using GDAL, R, GRASS GIS or SAGA GIS

I downloaded a NetCDF file that contains daily precipitation values from 1-1-1950 to 30-6-2013. The raster has 23191 bands. http://eca.knmi.nl/download/ensembles/download.php My goal is to analyze ...
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How to integrate SAGA Python Modules into ArcGIS Desktop?

I have been having a look at SAGA (http://www.saga-gis.org/en/index.html) and it seems to have some nice tools for geoprocessing. I was wondering if anyone out there has had any luck bringing SAGA ...
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34 views

SAGA GIS Channel network crash

So, i had this very weird bug while treating my dem data lately. I used SAGA to create flows channel networks on a dem i acquired a little while ago. Preprocessed it using sink route detection and ...
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92 views

How to read .asc format DEMs that have headers with #comments

I have around twenty 2 GB DEMs (xyz) in .asc format. The header has 13 lines of metadata, and then the basic data in three columns # # The DTM grid had lower left (southwest) corner coords: # X ...
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1answer
34 views

Why does SAGA raster calculator interpolate between cell values?

I am hoping for a bit of help with a raster calculator issue that is puzzling me. I have a raster layer with a series of integer values (classes) for each cell. I am trying to use the SAGA Raster ...
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9 views

How do you view an image (tiff) in SAGA 2.2.5

I was to open an image (tiff) in SAGA 2.2.5 but it is failing to open. How can I do it? It is not visible even if it shows that executed successfully
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44 views

Why do I get this anomaly (vertical line) in my TWI raster?

I have derived TWI using SAGA GIS, Have a look on the center of the image, a vertical line goes through it from top to bottom. Anyone else confronted this issue?
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17 views

SAGA Flow Direction input

I have several .adf files making up a DEM in ArcGIS, i want to input this DEM into SAGA to run some different Flow Direction algorithms. Is there a way to convert these files to .asc to allow me to ...
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106 views

Variable window (“kernel”) size for raster processing

I'd like to use differently sized windows as I process (a.k.a. filter) a raster, with the size varying according to latitude. There are tools that allow a user to specify custom windows (e.g., ...
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Calculating longest flow path and avg. slopes for catchments with qgis?

I am a hydrologist and there are 2 important pieces of information I need for modeling. I need to know the longest flow path for each sub catchment in my area of interest and I need to know the ...
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1answer
873 views

Getting Negative Topographic Wetness Index (TWI) values in SAGA GIS?

I am getting negative topographic index wetness values in SAGA GIS - anyone else every get this? Not all negative values, but the minimum of the TWI range is negative for some steep watersheds we are ...
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1answer
739 views

Converting LAS file to .asc DSM? [duplicate]

I want to count trees in SAGA GIS and I am trying to follow the steps described in Counting trees using segmentation and vectorization in SAGA Gis from dominoc925.blogspot.com (05th, March, 2012). ...
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15 views

Mosaic overlapping, irregular raster layers produces grid of NaN

I am trying to use the SAGA - Mosaic operator in QGIS 2.14.0 to mosaic two viewshed raster outputs I have. The viewsheds are irregularly shaped and overlap considerably, thus the need for the Mosaic ...
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Georeferenced Image Overlay and export to new image

I have two Geotiffs (one satellite image, one clipped image). I want to put the clipped image over the satellite image, because it shows flow velocity from this shown glacier (see image below). I ...
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1answer
30 views

Catchment boundary polygon from catchment area raster

I am trying to generate a catchment area polygon from a digital elevation model. I am using SAGA tools in QGIS and used the Flow Accumulation (Flow Tracing) tool to generate a catchment area raster ...
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67 views

SAGA Watershed Segmentation in QGIS: Error 1

I am trying to run a watershed segmentation using the SAGA plugin in QGIS. Unfortunately, every time I have tried to run this on a specific file QGIS freezes. The log output reports the following: ...
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312 views

Creating New Modules in Saga GIS

I have recently started development with SAGA and have run into some difficulties. I have checked out the svn code base and have successfully compiled in VS-10 (except the project ViGrA). Now I just ...
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370 views

Debugging errors of SAGA interpolation algorithms in QGIS 2.0 Processing

I encounter recurrent problems with the geoalgorithms that perform interpolations. No matter technique I use I end with the following errors. As state in OGR tab QGIS is unable to open a file in C ...
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23 views

Does SAGA in QGIS processing can support no ascii name?

From Qgis, I am calling through Processing the Saga algs "clipgridwithpolygon" raster_inside_poly = processing.runalg("saga:clipgridwithpolygon", my_raster_temp, ...
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12k views

How to calculate raster statistics for polygons?

how can I calculate sums, averages etc of raster-points (multi-band) per polygon of a vector-layer. I was told that this is called "zonal statistics". I tried that with QGIS first. There is a way to ...
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32 views

Importing TIFF to SAGA [closed]

I'm trying to import a large GeoTIFF (~1.2 GB) into SAGA GIS for processing as a grid using Import/Export - GDAL/OGR -> GDAL: Import Raster, but it keeps crashing. I'm using the 32bit OSGEO4W SAGA ...
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4answers
710 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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50 views

Solar radiation flux at 5 minute interval using GRASS GIS r.sun

I have been trying to estimate instantaneous total solar irradiance(w/m2) at five minute interval for a day (eg. 21 sept). I can do this in SAGA GIS by using "moment, mode 1" and running the solar ...
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36 views

How to delete by attribute from shapefile in SAGA command

I have lot of shapefiles to erase polygons with same attribute form them. It is usually an easy task when do manually, but how can I use SAGA-GIS command? Any help?
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3k views

Performing Ordinary Kriging in SAGA via QGIS SEXTANTE Plug-in?

I'm trying to learn how to apply the kriging analysis in QGIS using the SEXTANTE plug-in and SAGA tools. It appears that I have my SEXTANTE and SAGA folders configured properly according to the user ...
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1answer
577 views

QGIS 2.12 & Ubuntu 14.04 SAGA installation not found

Installing QGIS 2.12 on Ubuntu 14.04 from the debian trusty ppa. Upon opening QGIS I notice the following error under the Processing tab: Problem with SAGA installation: SAGA was not found or is not ...
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Processing toolbox on Google Cloud compute engine

I used to utilize the QGIS python console to do GIS batch operations on my local machine. Computation times are rapidly increasing and I'm switching to a virtual machine solution in the cloud. How ...
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1answer
46 views

Where does the output of a grid volume run in the Saga tool/ Qgis end up?

I have tried to do a grid volume run with the Saga grid calculus - grid volume function. After the run the window closes and nothing seems to happen, no message, no new layer or information appear. I ...
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1answer
125 views

strange output from RSAGA topographic wetness index

I am trying to generate a topographic wetness index raster with the RSAGA package in R. The output I am able to generate does not make sense to me, as it has a large number of NA cells and I wonder if ...
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40 views

How to chain several conditions in SAGA raster calculator

Is there a way to use an AND statement within SAGA raster calculator expression to include several conditions in the same operation? I have 3 rasters, the statment should be: If (A = 0 and B = ...
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1answer
126 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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2answers
764 views

How to de-noise a DSM

I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any ...
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5answers
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How to set all pixels with value <= 0 to “nodata” in DEM raster?

I have a DEM raster with pixel values between about 3000 and -0.0003. I need to set all pixel with a value of 0 and smaler (<=0) to "nodata" (for later raster calculations and to reduce the ...
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3answers
100 views

Dissolve overlapping polygons in SAGA

I've got the following (2D!) situation of overlapping polygons: I would like to have the polygon border dissolved such that I have only one polygon left. I thought this was a definitive case for ...
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3answers
3k views

How to configure QGIS and SAGA on Ubuntu (12.04 and others)?

During the past weeks, I have tried QGIS to recognize SAGA via the processing toolbox, both being installed from the ubuntugis-unstable repository. I have tried this on several virtual ubuntu ...
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2answers
225 views

Least cost path between various points QGIS

Is there an easy way to find the least cost path (LCP) between various points in an open source GIS? This question has actually already been asked here: How to find a least cost path through several ...
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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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SAGA-Inverse Distance Weighting in QGIS - How to Set Minimum Number of Points?

I am analyzing a postGIS point dataset in QGIS version 2.8.2, about 200k features total. To calculate weighted average values I am using the Inverse Distance Weighted interpolation technique. However, ...
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3answers
711 views

LiDAR data density, returns per square meter

How can I compute a raster showing the number of return points per square meter using SAGA GIS or other open source software? My goal is to obtain a mask which would show me the places (cells) ...
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1answer
57 views

Check QGIS processing Saga version from a plugin

I am writing a QGIS plugin using SAGA by Processing. Is is possible to test whether SAGA is installed and which version is on? For GDAL, it's OK with: processing.tools.raster.gdal.__version__
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1answer
848 views

How to make GRASS and SAGA tools capable to use in QGIS?

I installed QGIS, GRASS and GDAL by OSGeo4w package, and as I finish the installation, I want to use GRASS tool, I face this problem: But I already installed GRASS and SAGA, how to make those tools ...
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1answer
227 views

No Saga in QGIS 2.12

After installed QGIS 2.12 I don't have SAGA in Processing Toolbox anymore and I need it bad. Am I blind, can't find it or something went wrong? Any suggestions please? My OS is Win 7 64 bit.