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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62 views

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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68 views

SAGA Tool in QGIS Error: Load table: Proj.4-WKT Dictionary… failed

I have some problems with running SAGA tools in QGIS. I've downloaded and installed the software via the OSGeo4W Installer. It downloaded QGIS 2.12 and Saga 2.1.2. I wanted to use the Tool "Shapes To ...
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146 views

Segmentation fault in SAGA GIS

When I try to launch SAGA GIS I get this error: "segmentation fault (core dumped)" How can I solve this problem? I am using Lubuntu 14.04 64-bit.
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80 views

Error on running Saga GIS inside QGIS

I have installed QGIS (2.14.3-Essen) along with SAGA GIS (Version: 2.2.7) in Ubuntu (14.04 trusty). I am trying to fill the sinks in a DEM in QGIS processing using SAGA provider. I have used both the ...
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48 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, 0....
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93 views

SAGA hydrological analysis in QGIS 2.8 on Mac

I am running QGIS 2.8 on a Mac machine and I want to calculate the catchment area using SAGA - Catchment Area. It starts running but after a while when QGIS wants to open the generated files there is ...
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100 views

QGIS algorithms do not work on copies of shapefiles?

I'm using QGIS 2.6.0. I'm trying to run various algorithms such as "SAGA/Shapes-points/remove duplicates" & "SAGA/Shapes-Grid/Add grid values to points" through the sextant toolbox. When I run ...
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314 views

SAGA is not working within sextante (QGIS processing installed in Ubuntu)

Recently i decided to start working in Ubuntu (version 14.04). My first step was to add the ubuntugis-unestable repository, and then proceed to install SAGA, GRASS, OTB, QGIS and the bindings between ...
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986 views

QGIS cannot open output layers

I have problem with QGIS 2.0.1. Everytime I run tool from SAGA or GRASS, I get exactly the same error, for example: Oooops! The following output layers could not be open Channel Network: /tmp/...
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34 views

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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79 views

Improve tree extraction method

I want to extract trees from a given normalized Digital Surface Model (nDSM) in SAGA GIS. My workflow is the following: Applying a Gaussian Filter to the nDSM with search radius with standard ...
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84 views

Error when using SAGA's “topographic correction” algorithm in QGIS

I'm trying to do topographic correction of Landsat images using SAGA's "topographic correction" algorithm from QGIS' processing toolbox. I was able to do it using Minnaert Correction with slope and ...
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116 views

how to orthogonalize building outlines

I'm looking for a way to orthogonalize building outlines which I've extracted from a high-res DEM. I'm using the FOSS GIS stack (QGIS, GRASS, SAGA, PostgrSQL, PostGIS) and can code in Python (or Java)....
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116 views

Why is SAGA kriging slower in QGIS than in SAGA itself?

I'm using QGIS for a while. In my opinion the SAGA kriging tool (processing toolbox) is very slow. Is that an QGIS issue? I tried to interpolate a point layer with 300.000 points (I know it is big) ...
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124 views

Batch raster calculation of slope and aspect in SAGA

I am relatively new to the SAGA software, I have only used it for small amouns of data, and for basic calculations. My data is obtained by mapping certain areas in GoogleEarth, then, overlaying the ...
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136 views

QGIS Upslope/Downstream Areas

I am trying to locate areas upstream and downstream of a point of interest in QGIS in order to determine possible areas of origin upstream and areas of impact downstream. I have used a DEM to create ...
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394 views

Problem loading output layer QGIS

Every time I run operations with temporary file output from the graphical modeler, I get the following error message: Oooops! The following output layers could not be open CLIP: C:\Users\Amine\...
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208 views

Extra row and column in a raster after GDAL grid import

I'm exporting an ESRI grid to TIFF format and after that I'm reading this exported raster file into SAGA GIS. However when Saga reads this file in there appears to be an additional row and column in ...
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83 views

Re-projecting WGS84 to OSGB in SAGAGIS

I took some points with a GPS, and I'm trying to convert from GCS to OSGB 1936 British National Grid in SAGAGIS. I'm working with a shapefile. To reproject the vector layer to the OSGB projection I ...
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431 views

Watershed Segmentation SAGA-GIS

I'm trying to segment a topographic map to vectorize it. I'm using the watershed algorithm of SAGA-GIS. It's working fine with polygons, but with roads or contour lines is not working properly. Here ...
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482 views

OGR VRT MSSQL example

I'm trying to import vector data into SAGA GIS from a SQLExpress 2008 server. Firstly is this possible? I would have thought using an OGR VRT layer would have been the way to do it, I've attached a ...
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24 views

SAGA Merge raster layers error

I have 198 tiles of a DEM from which I want to extract contour lines, but doing the operation 198 times is ungainly. I tried SAGA's Merge raster layers, but it stops into this error: Oooops! The ...
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44 views

Error with SAGA's Topgraphic Correction

I am using QGIS 2.14.2, trying to perform a supervised classification on a rapideye image with the SCP plugin. To improve my classification im trying to work with the SAGA's topographic correction. I'...
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23 views

“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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30 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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40 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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45 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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18 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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49 views

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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25 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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31 views

How is “flat” defined in SAGA

SAGA has a feature that determines flats. Does anybody know how they define a flat? If I start with a raster, each pixel is flat - so it has to be more sophisticated than that. I would like to be ...
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101 views

Delineate watershed using manual points in RSAGA

I'm currently trying for an automated solution to delineate watersheds within a large basin. I have a collection of locations (X,Y coords) for various tributaries reaching a larger river, and the end-...
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131 views

Trouble with kernel density estimation

I have been trying to find out how to make the SAGA and GRASS kernel density tools work in QGIS 2.8. I have had a lot of trouble trying to get them to work as they produce useless results seen below. ...
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94 views

QQIG/SAGA “merge shapes layers” algorithm removes underscores/pluses from layer names

I have a bunch of layers that are named layername_number+number that I want to merge. I need their names as source attribute so I used the "merge shapes layers" algorithm found under SAGA in the ...
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70 views

GRASS and SAGA CentOS Linux release 7.1.1503 (Core)

I have a problem. I am developing a standalone app using QGIS but my script imports GRASS nad SAGA plugins and I have error to create the maps. I have CentOS Linux release 7.1.1503 (Core). SAGA is ...
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90 views

Why does the “local maxima” module in SAGA GIS put so many “maxima” points on lakes and plains?

SAGA GIS puts too many maxima points on plains and lakes. Why does it happen? Is there a way to avoid this? It's not really a big problem (the value is correct) except for the size of the SHP files in ...
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113 views

Put output of SAGA algorithm of Processing model in R script

I'm trying to combine the Variogram Cloud model of SAGA with an R script inside a Processing model. First, the R script is: ##Vector processing=group ##showplots ##Layer=table ##X=Field Layer ##Y=...
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231 views

SAGA Raster Calculator, ifelse doesn't return specified value exactly

First time caller, long time listener.... I am using the SAGA Raster Calculator in QGIS 2.6 to change NaN values to zero and that part is working great, however the specified 'if' value is being ...
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68 views

How to load “soil types” in QGis?

I want to show soil transmissivity per pixel. Thus, I determine water holding capacity of each pixel (ignored other effective parameters). Respectively, I wonder, What is the soil data format and How ...
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116 views

SAGA GIS - raster image from Civil 3D

I am a new user of SAGA GIS software. I need to interface the Civil 3D 2015 and Hec Ras software in order to create a flooding map. In order to put in communication the two softwares, I have to use ...
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58 views

What is the background processing of rainfall thresholding?

I want to create a flood map using Quantum GIS. First of all I create catchment area (flow accumulation). Then, I delineate a Channel Network by applying a threshold to flow accumulation. So I want to ...
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152 views

QGIS 2.6 SAGA Processing Algorithm, “Add grid values to shapes”, produces NULL Values

I'm using QGIS 2.6 Brighton on Windows with SAGA 2.0.8 installed using OSGeo4W. I have the same versions installed on OSX as well which is not having this problem. On Windows, I'm trying to extract ...
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158 views

How to calculate the Vertical Distance to Channel Network in ArcGis?

In Saga there is the tool "Vertical Distance to Channel Network". Is there a way to produce the same data in ArcGIs? With con("flowacc" > xx, 1) I was able to create the Channel Network. I am ...
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580 views

QGIS SAGA Channel network error: Input layers do not have the same grid extent

I am trying to follow along with this exercise using my own DEM. I have done the first step, creating the catchment area, with no trouble. When I try to run the Channel network algorithm, however, I ...
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185 views

QGIS processing framework SAGA NaturalNeighbor in external Python Script - No Output

I want to build a little script, which generates a NaturalNeighbor grid based on a point Shapefile. The script runs within my PyDev environment without any error messages, but no outputfile is created....
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36 views

Exporting landcover clasiffication from ENVI to SAGA

I have basic knowledge in remote sensing and GIS. I have generated landcover map in ENVI 4.7. How can I transfer or Export/Import this into SAGA so that I perform other functions in SAGA. I want to ...
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281 views

What steps does SAGA GIS take when calculating Topographic Wetness, specifically when handling depression filled (by ArcMap) DEM

I am a grad student involved with hydrological modeling. In the model I work on, we are calculating the Topographic Index (TI; without transmissivity - or set to 1) using Quinn's MFD algorithm. We do ...
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134 views

Is the SAGA tool Basic terrain analysis included in Processing?

I can't find the saga tool Basic terrain analysis in the Sextante/processing toolbox. Is this not included or is there a chance to install it?
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192 views

Defining the boundary of a catchment area

I digitized contour lines from topographic maps and created a DEM. With the DEM, I estimated the boundary of a catchment area. Estimated positional accuracy of topographic maps is RMSE = 65 m, with a ...
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97 views

MSHP file from SAGA tough to delete

After running a SAGA line dissolve process in QGIS, an MSHP file is created (amongst other things). Fine by me, though I'm not sure what it's used for (metadata in XML format?). Problem is that it can'...