Questions tagged [saga]

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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2
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2answers
145 views

Seeking for a solution to convert GeoTIFF to 3d WKT

I am trying to convert some DEM in .tif image to polygon geometries representing 3 dimensional triangles that is Well-known text (WKT) - 3D (x, y, z) I was able to use SAGA to convert my GeoTIFF ...
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0answers
28 views

Python function like SAGA Grid Gridding?

For a python script, I'm searching for a function that does the same as SAGA Grid gridding, an exponential interpolation on GeoPandas GeoDataFrame. Does anyone know one?
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1answer
101 views

Load a SAGA RGB composite in QGIS

I have created a RGB composite in SAGA GIS using the RGB composite tool. A one band raster is created, which can be visualised in SAGA using the option RGB coded values. When I try to import this ...
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1answer
74 views

Not correct numeric value error using Multilevel B-Spline interpolation with SAGA and QGIS?

This is the generated log: Processing algorithm… Algorithm 'Multilevel b-spline interpolation (from raster)' starting… Input parameters: { 'DATATYPE' : 0, 'EPSILON' : 0.0001, 'GRID' : '/Users/...
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0answers
137 views

Avoiding artefacts by pixel filtering in a raster

I have a DEM with a spatial resolution of 2 meters with a lot of areas with no data. I want to fill those gaps in order to use the whole DEM. I used the 'close gaps' tool in QGIS (it's a SAGA tool) ...
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0answers
55 views

Native QGIS Dissolve tool not compatible with SAGA Split Lines at Points tool

I am trying to use the SAGA "Split lines at points" tool within QGIS. I first had a polyline layer with line segments/features of arbitrary length. I then did the following: Dissolve using the native ...
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1answer
389 views

Watersheds in SAGA Fill Sinks Wang & Liu tool

I'm delineating some coastal subbasins using open source software. I have asked a similar question before (Delineating coastal subbasins using SAGA GIS or GRASS in QGIS?). I found that using SAGA Fill ...
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1answer
126 views

Large Scale Watershed Delineation

Using QGIS,I attempted Africa's watershed delineation taking the following steps: Downloaded DEM from earthexplorer USGS (GTOPO30) Created a mosaic of the downloaded DEM Reprojected the mosaic ...
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0answers
28 views

Using graphical modeler script via command line

I have made a script through the graphical modeler and I exported it. This is the code that it exported: [Python code] https://imgur.com/a/ivgWXUh How do I run this code outside of QGIS? Which ...
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1answer
234 views

QGIS SAGA “Natural Neighbourhood” gridding error

I'm having issues with saving my grid out to file. Every time I try, I get the error " The output layer could was not generated" C:\Users\Name\Documents\QGIS\Rav.tif 'Check error log for more ...
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0answers
31 views

Obtaining reflectance value after supervised classification in QGIS/SAGA

I want to extract the reflectance values of my classes/training inputs but after supervised classification i.e post classification. Is there any tool or process to do it in QGIS/SAGA
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2answers
138 views

v.surf.bspline and Interpolation(cublic spline) persistent errors in QGIS 3.2 & 3.3

I'm new to QGIS and as such I'm pretty hesitant to post anything, but I cannot for the life of me figure out why two raster creation techniques are not working. For the v.surf.bspline GRASS algorithm:...
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2answers
129 views

How do I run SAGA algorithms in PyCharm? [closed]

Is there anyway I can input a raster and number and then use the SAGA algorithm "Fill Sinks (Wang and Liu)" on the raster through an IDE such as PyCharm? How would I go about calling the algorithm? ...
2
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1answer
428 views

QGIS 3.2: Processing toolbox tools from SAGA never run

I am having major issues in getting tools to run from the toolbox in version 3.2. In essence all but very simple algorithms like 'Split RGB' return errors and do not run. I cannot get any openCV or ...
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1answer
388 views

Calculating Specific Catchment Area in QGIS?

I have tried to calculate the Specific Catchment Area in QGis from Specific Catchment Area and Flow Width Tool available through Saga. However, I got just SCA product with valour 0. I got a reasonable ...
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50 views

Running QGIS Processing Modeler Script

Is there anyway to run an exported script from the processing modeler in PyCharm? How do I go about installing the necessary packages to run a function?
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0answers
72 views

Generate stream network for every pixel of flow direction as a polyline shapefile based on the raster cell value

I have a flow direction raster (coded with ESRI flow directional encoding scheme) and I want to generate stream network for every grid cell of flow direction raster as a polyline feature based on the ...
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1answer
65 views

Merging two processes in QGIS3 to one?

Is there any way to merge several processes in QGIS3 into one process? Or is there a way to look at the source code of different processes under QGIS3 and combine them under one function? I am ...
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1answer
119 views

What layers are produced by SAGA Potential Incoming Solar Radiation?

I estimated the Potential Incoming Solar Radiation in SAGA. The tool creates a file "direct insolation" and "diffuse insolation". When I export these files as .tif, a layerstack of 3 raster layers is ...
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3answers
173 views

Finding source code of “fill sinks (wang and liu)”

I would like to use the source code of "fill sinks (wang and liu)". I checked through QGIS3 folders, but could not find much related to it. Anyone know where the code could be?
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2answers
594 views

Convert sgrd (SAGA GIS format) to raster or ascii or with R

I need to convert a sgrd file to tif or ascii using R. I converted a big sgrd file (1.4 GB, 376521831 pixels) to ascii using the package RSAGAbut it takes too long (approx. 45 minutes): rsaga.sgrd.to....
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1answer
172 views

Ordered weighted averaging error: can only concatenate list (not “str”) to list

I am trying to perform an ordered weighted average on two rasters in QGIS 3.0.3 (as a trial run for doing it on more than two rasters). But I keep receiving the following error code: Traceback (most ...
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1answer
258 views

Coordinate system change in SAGA

I know it is an overasked question but I do not find anybody able to explain properly how to do that in SAGA 6.3. The problem is that my shapefile, i.e. the borders of my country, do not overlap ...
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0answers
176 views

Empirical variogram plot in QGIS

I am trying to do kriging on mortality rates using QGIS (I have version 3.0 but I downloaded the 2.18.20 to be able to follow the web documentation and most of the answers here). From what I have ...
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1answer
44 views

How can I adopt updated qgis\python\plugins\processing\algs\saga\description txt files?

I have one question: How can I adopt updated qgis\python\plugins\processing\algs\saga\description txt files? The rest of this text is "enough detail to identify an adequate answer". I will try to ...
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1answer
49 views

calculate 'predicted class' raster in QGIS

I have six raster layers that represent the probability of each pixel belonging to a specific vegetation type. I would like to use these to generate a new raster where the value of each pixel is the ...
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1answer
44 views

Interpolation of holes resulting from DTM groundfiltering of SfM pointcloud

I am wondering if there is an efficient interpolation method to close the holes in a dtm resulting from groundfiltering. At the moment I am directly interpolating the point cloud to a raster using ...
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1answer
116 views

SAGA-GIS 2.3.1 Segmentation Fault on launch

I recently installed QGIS, GRASS, and SAGA-GIS-LTR onto a Manjaro (Arch Linux-based) system in order to make use of their newer libraries. While most of the software is working fine I did need to ...
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0answers
185 views

QGIS 3: saga algorithm in console

I'm trying to use the saga algorithm 'quadtree structure to polygon' (with points to get polygons), in the python console. But I think I'm not able to set the parameters correctly. When I call the ...
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0answers
205 views

Saga Catchment Area not giving expected (useful) output

I am identifying a catchment network from a DEM in QGIS3 (v3.0.3) (on a mac v10.13.4), however the step to identify the Catchment Area is not working. I have an input DEM, with layer CRS set to ...
2
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1answer
247 views

Ordered Weighted Averaging problem

I want to do an Ordered Weighted Averaging (OWA) analysis using SAGA in QGIS (not by using pyqgis) as a suitability assessment for recreation/restoration of specific habitats. There's a number of ...
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0answers
129 views

QGIS SAGA Gaussian Filter brings error when run

Every time I run the SAGA Gaussian Filter tool, I get an error. I am trying to filter a raster file indicating a risk index (GeoTIFF, 32-bit float) in order to smooth it. The log message I get is ...
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0answers
168 views

Saga difference vector tool

My QGis Difference tool doesn't work really well, it gives me lots of little squigly lines. i read in the link below there is such a thing as a vector diffence tool from SAGA, but i can't find it. ...
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0answers
212 views

Creating sub-watershed within a basin

I am a beginner to QGIS. My problem is I tried to create sub-catchment within a basin by using provided point datasets (river gauge location). In total, I have 12 measuring points (i.e 12 pairs of x ...
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0answers
49 views

QGIS 2.18 SAGA Change Data Storage

I tried to use Change Data Storage to change the bit depth of some rasters, but it doesn't work or gives me vague errors I first tried to batch convert some rasters to unsigned 1 byte interger, I ...
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1answer
209 views

Making all values in raster same using QGIS?

I need to convert all the values in a raster to one certain value. How can I do this? (I tried using raster calculator, but any operation that would result in a raster having all one value makes it ...
7
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2answers
187 views

Prevent SAGA in QGIS 3.0 from creating certain outputs?

I'm wondering if there is a way to prevent SAGA from generating temporary files. For example, if I just want to generate a slope map using SAGA I have to wait for all 11 other grids to get processed. ...
2
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0answers
121 views

Saga clip raster with polygon missing cells entirely within the polygon

I am using SAGA's Clip Raster with polygon tool in QGIS 2.18.4. It is missing an entire row of cells which are entirely contained within the clipping polygon (see image, original DEM in colours, ...
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0answers
99 views

Setting maximum slope/flow length in flow accumulation using SAGA?

I like to limit the slope length in SAGA GIS. In other words, the flow accumulation should only account for a specific length until a subsurface flow initiates and surface flow stops. Actually, I ...
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2answers
383 views

Compute flow accumulation only from flow direction?

I am looking to calculate flow accumulation from a flow direction raster. In ArcGIS there is Flow Accumulation (http://desktop.arcgis.com/en/arcmap/10.3/tools/spatial-analyst-toolbox/flow-accumulation....
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1answer
403 views

QGIS 3 and SAGA 3.0+ Integration

I've looked all over the net and I'm wondering if there are any plans by the QGIS developers to integrate some of the newer versions of SAGA available in the repository and as binaries on the project'...
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0answers
332 views

“Cross-classification and tabulation” tool is not outputting a table

In QGIS3 I’m trying to use SAGA’s "Cross-classification and tabulation” tool from the processing toolbox, and based on the documentation (http://www.saga-gis.org/saga_tool_doc/6.3.0/grid_analysis_13....
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1answer
54 views

Removing all pixels at apprx. ground level in orthomosaic? [closed]

At the moment I am processing an orthomosaic from a plantation and I would like to remove all pixels at ground level to just keep the plants captured on the image. I would prefer to be using QGIS. ...
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1answer
196 views

Batch processing in QGIS SAGA Algorithm

i'm struggling to run batch processing multilevel b-spline interpolation for my surface area the below error message keeps on poping up after the process> Processing algorithm 1/3... Algorithm ...
0
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1answer
464 views

Interpreting results in legend, SAGA GIS or QGIS? [closed]

Can somebody explain to me what units of measurement do I get in the results of analysis, ground morphometry in SAGA GIS software or through a plugin in QGIS? for example: Terrain ruggedness index (...
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0answers
109 views

Implement Basic Terrain Analysis(SAGA) by Python

Basic Terrain Analysis is in Processing Toolbox of QGIS and it has many output results, like Channel Network, Drainage Basins, Valley Depth, etc. I just want to get Channel Network among these results....
3
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1answer
757 views

volume of a raster

I have two rasters from which i want to calculate the volume difference between the two. I made a 3rd raster that shows the difference between the first two rasters. So i think calculating the volume ...
3
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2answers
212 views

Getting the average of maximum values from raster (tree top segementation)

I've got raster with elevations of trees in a forest. I would like to find out the average tree height of all trees in a given area. Because of the geometry of a tree top (which is like a cone and ...
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0answers
35 views

SAGA Maximum Flow Length problems with the Coordinate systems

I'm new to SAGA. I've got a srtm data set from europe and want to charge the maximum flow length especially from the river Elbe. The data is in WGS84 So first I ran the tool "Fill Sinks"(Wang & ...
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0answers
132 views

Add polygon attributes to points fails to create layer

I'm trying to add polygon attributes to a point file with a lot (~370,000) of points in QGIS v3.0.0. I first tried using the point sampling tool, which I've used with success pulling the values from ...