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++.

Filter by
Sorted by
Tagged with
1
vote
0answers
13 views

QGIS SAGA Overland flow distance to channel network not working

I am trying to run the QGIS SAGA tool "Overland flow distance to channel network" with a DEM and the channel network raster developed from this same DEM using the SAGA tool "Channel network." However, ...
3
votes
1answer
45 views

Using SAGA GIS 7.X modules in QGIS

Is it possible (and how) to use the SAGA GIS 7.x modules in QGIS (as well as for GRASS GIS)?
1
vote
0answers
43 views

SAGA: could not initialize data objects (QGIS 3.6, Mac 10.14)

I was trying to generate a catchment area from a DEM and got the error message: The following layers were not correctly generated.<ul><li>/var/folders/ft/rbsnpzy96r76t8rkj5fdtzc40000gn/T/...
1
vote
1answer
17 views

Using Formal Class RasterLayer as RSAGA input and otput

Is there a way to use the data from the R global environment object as input for an rsaga.geoprocessor alghoritm? And if yes, can be the output also saved as a same object? I am writing chain ...
2
votes
0answers
37 views

VRM tool QGIS error generating layer

I am trying to use the VRM tool in QGIS of the SAGA package. Every time I get an error message: layers could not be generated. I tried different input rasters (DEM and DTM) and kept other settings ...
1
vote
1answer
49 views

Error creating DEM with Nearest Neighbour tool in QGIS?

I have an issue when I am creating a DEM with the tool natural neighbour on QGIS. When I extract my data directly on Qgis I have no issue creating a DEM. My points are coming from different sources ...
2
votes
0answers
46 views

Inaccurate raster values from “SAGA Extract Raster Values to Points”

I am perplexed by the results generated by the SAGA 2.3.1 Extract Values to Points tool in QGIS 2.18. I am working with Vegetation Index raster layers, which means the values are between -1 and 1. ...
3
votes
1answer
124 views

Sentinel-1 SAR image is displayed upside down

I am looking at Sentinel-1 SAR image downloaded from ESA Copernicus - dhus location around south of Tokyo, Japan. File format is GeoTIFF. It looks good in QGIS. However, if I use SAGA, or SNAP, or ...
1
vote
0answers
25 views

No SAGA folder in processing options dialog box

I am using QGIS 2.18. I am facing this error while using EasyAHP: "The error occured during calculation. Please make sure that Processing Toolbox's SAGA provider is installed." But, I guess the ...
3
votes
1answer
68 views

Is there an equivalent to “keep inner boundaries” in QGIS 3?

At QGIS 3.4.7, I have some polygons that are overlapped and I use Polygon dissolver (by attribute) from SAGA to dissolve then and I check the option "keep inner boundaries", but this tool takes too ...
3
votes
1answer
46 views

Cheapest path through polygons and lines from point to point

I want to find the cheapest path or the least cost path from one point to another point. The points are part of a vector map and do not lie on a network. All features being part of the map have ...
1
vote
1answer
72 views

Raster Volume Returning Wrong Volume

I have a clipped surface using Washington State Plane North (feet) added to a QGIS project using the same CRS. I am trying to calculate the area under this surface (a dirt pile) using SAGA Raster ...
0
votes
3answers
83 views

Converting raster pixels to vector cells?

Is there any way to convert raster pixels to vector cells? I mean each pixel to a polygon. I tried the SAGA tool 'Raster values to points' by choosing cells option instead of nodes option. As a ...
3
votes
0answers
62 views

Extracting GeoTIFF colours and adding to equal geometry shapefile

I have the following map in .png-format that I would like to replicate, but I cannot obtain the original data. The map shows the current water supply vulnerability for local municipalities in South ...
1
vote
1answer
72 views

Analytical hierarchy process tool - SAGA. How to configure Pairwise comparisons table?

What is the configuration and extension (.txt, .csv ...) of the Pairwise comparisons table file requested by the SAGA AHP tool- Analytical Hierarchy Process - in QGIS? Are there examples of ...
0
votes
0answers
52 views

Easy AHP returns error because it can not find the SAGA 2.3.2 folder

When I try to complete the AHP in QGIS 2.18.27 using easy_AHP, the plugin responds: although the SAGA tools are working perfectly by the Processing Toolbox. The SAGA configuration options in QGIS ...
0
votes
1answer
77 views

QGIS 3.4 Stream delineation problem, lines running too far into ocean

I am using QGIS 3.4.4 Madeira version trying to delineate the stream and catchment areas of a small Bay in Honduras based on the technique of Hanz van der kwast tutorial "Stream and Catchment ...
1
vote
1answer
68 views

Getting QGIS Model Processing Raster Calculator Error?

I am using "raster calculator" tool of the saga in my model. The tool correctly executes raster operation like "a * 2" in value formula option but the same expression is not executed pre-calculated ...
1
vote
1answer
73 views

Relief Segmentation Tools, SAGA

Where can I find documentation on the tool Relief Segmentation of the library Terrain Analysis?
3
votes
2answers
135 views

QGIS SAGA functions failing “… following layers not correctly generated. …” [closed]

I've been having an issue with the SAGA functions for a while now, I believe since upgrading to one of the early 3.x versions. No matter which function I use they all fail with the same error (...
1
vote
0answers
45 views

Error using SAGA raster creation tools. Input layer error: points?

I have a shapefile containing x,y,z values as a point vector layer. I want to interpolate these points to create a DEM. For that I use SAGA natural neighbour algorithm. However, I am not successful ...
0
votes
1answer
318 views

QGIS 3.4.4 and 3.6 SAGA Tools all not working with same error

C:\OSGeo4W\bin>exit Execution completed in 12.17 seconds Results: {'SHADE': 'C:/QGIS/output/HS.sdat'} Loading resulting layers The following layers were not correctly generated.C:/QGIS/output/HS....
1
vote
0answers
89 views

SAGA 2.3.1 makes QGIS 2.18 crash on Ubuntu 18.04 [closed]

On Ubuntu 18.04, using packages provided by universe repos QGIS 2.18.17+dfsg-1 SAGA 2.3.1+dfsg-3build7 When starting any SAGA algorithm, QGIS crashes with a "Segmentation fault" error message. We ...
1
vote
1answer
128 views

LS Factor in SAGA (slope units)

In which units do I have to calculate Slope to use as an input for the LS Factor tool in SAGA (degrees, %, radians)? I couldn't find anything in the documentation.
1
vote
1answer
47 views

Piping one SAGA Raster Calculator output into another chaining algorithms in QGIS processing script?

I am using QGIS 2.18.15. I want to streamline multiple SAGA raster calculator calculations using the output of one calculation (not loading it into the table of contents) as input raster for the ...
3
votes
1answer
109 views

SAGA Raster Calculator in QGIS Algorithm script produces 'NoneType' object has no attribute 'crs'

I would like to produce a new temporary raster after a calculation with the SAGA raster calculator using a custom python algorithm script. This is my code so far: ##MaechtigkeitunterhalbeinerHoehe=...
2
votes
1answer
269 views

Layers not correctly generated using saga algorithms within QGIS 3.4.4-Madeira

I am trying to use a few algorithms that may be useful for my work, that are part of the processing tools packaged with the latest LTR 64-bit version of QGIS in Windows 10 64 bit.. However, all of the ...
1
vote
1answer
28 views

SAGA Raster Calculator processing script give error “name 'Rasterout' is not defined”

I am trying to build a custom script using things I have learned from this post: Number inputs as raster calculator variables in QGIS Modeler This is my script so far: ##Maechtigkeit unterhalb einer ...
1
vote
0answers
60 views

How to write raster in saga format with python

I try to write a raster file in SAGA GIS format (sgrd). My script is work but some information is missing in the final file (i.e output.sgrd). Here is script : from osgeo import gdal, ogr, osr import ...
0
votes
0answers
40 views

Radiometric correction of Aster Level 1T

We have to mosaic 70+ ASTER Level 1T imageries. I've splitted hdf data into 14 different tif's (3 VNIR, 6 SWIR, 5 TIR). As shown in the image imageries are of different time period. Question is, is ...
0
votes
0answers
23 views

Making QGIS model that iteratively creates several constant grids at once?

I'm looking to calculate the volume of a virtual reservoir from a DEM. I would use a constant grid (SAGA) to represent the ceiling, and I want to see the change in volume for each 1 metre interval. So ...
1
vote
0answers
57 views

Calculating maximum extent of debris flow from point with mean slope value

At a very large scale I perform a spatial analysis for which I have to apply mean slope criteria. These criteria allow me to calculate the maximum extent of an event (debris flow). I know that below a ...
1
vote
1answer
117 views

Using SAGA GIS for TPI classification?

I processed one country with TPI, and I got a certain Landforms classification of terrain. (Topographic Position Index (TPI) calculation as proposed by Guisan et al. (1999)). When I processed only one ...
1
vote
1answer
108 views

SAGA hydrology toolbox Error: select a library

Hi I am having trouble getting the SAGA hydrology toolbox running. Here when I try to fill sinks in the DEM a series of errors are flagged in the log file. This includes for 'select a library', 'DEM' ...
0
votes
1answer
145 views

Unable to perform SAGA point snapping to line on Win and Mac

I have been trying to snap points from a shapefile to a line feature from another shapefile. However, each time I do this, I get the following error(s) (depending upon the OS used): (For OSX El ...
2
votes
1answer
51 views

How to connect polygons to make a circle?

I created polygons from a raster on which I ran an edge detection filter. I turned the edges into a polygon layer (multipart splitted into single parts). The intention was to have circular polygons at ...
0
votes
0answers
37 views

SAGA_cmd crashes (using RSAGA)

I'm using SAGA-GIS to compute some terrain attributes with a DEM of file size 3.52 GB. I use Rsaga to operate on a 64 Bit operating system with an Intel(R) Core(TM) i5-2400 CPU @ 3.10 GHz Processor, ...
1
vote
1answer
34 views

How to add multiple layers to SAGA map view at the same time?

I need to visually interpret more than 50 grids, so I want to add them all to a SAGA map at the same time. If I right-click on a single layer, I can "Add to Map", but with multiple, this option is not ...
0
votes
0answers
108 views

Problems with SAGA on QGIS

I'm trying to perform an interpolation on SAGA in QGIS but every time I ran the tool (or any other SAGA tool for that matter) I got the following message: "The following layers were not correctly ...
1
vote
0answers
161 views

Error when running SAGA interpolation

I am running the nearest neighbour algorithm in QGIS 3.4.3. I have tried various parameters but the problem persists. I have also tried other algorithms (simple Kriging) and had the same problem. ...
2
votes
1answer
92 views

RSAGA error using rsaga.pisr2

I just downloaded SAGA and the RSAGA package for R. I would like to use the rsaga.pisr2 function to compute solar radiation for my region of interest. I am currently getting errors related to proj4 (...
1
vote
1answer
56 views

Adding two rasters in modeller

I'm trying to build a process model which uses a series of raster operations - Rasterize, Proximity, Raster Calculator. However, I couldn't seem to add two consecutive raster calculator processes. ...
0
votes
1answer
195 views

point thinning/point selection based on distance threshold in QGIS/GRASS

I need to thin a point vector later based on the distances amongst points. So I have a threshold and wish to omit all records but one that is below a distance D representing a distance between points. ...
1
vote
0answers
53 views

Promoting to multipart using PyQGIS?

I am creating a code that aggregates neighbouring polygons if they have similar value on the field 'DN' and if they are closer than 50 m.Then I want to iterate this 3 times. I could already get the ...
1
vote
1answer
194 views

Choosing parameters for SAGA Wetness Index?

I've been working with SAGA GIS to calculate the Topographic Wetness Index of an alpine catchment. I am using the tool Terrain analysis > Hydrology > SAGA Wetness Index because, compared to ...
2
votes
1answer
140 views

Clustering spatially connected polygons so all clusters have approximately the same size

I want to group together polygons from a shapefile a way that all the clusters formed contained approximately the same number of polygons. The problem is that the source polygons have vastly ...
1
vote
1answer
125 views

QGIS 3.2 SAGA Raster Values to Points: ERROR: Missing Parameter Value

When I try to run the saga:rastervaluestopoints tool in the QGIS 3.2 Python console it returns the following error (see below). I can't figure out what's going wrong. The tool works when running it ...
1
vote
0answers
45 views

SAGA_CMD.exe Bad image

In QGIS 3.0, 3.2 and now 3.4 I get the following error message saga_cmd.exe bad image C:\windows\system32\vcomp140.DLL is not designed to run on Windows or contains an error. I didn't have the ...
0
votes
0answers
88 views

Calculate the area of the drainage basin upstream of a point [duplicate]

I have the point location of vegetation surveys conducted on a river network. I would like to calculate the area of the contributing drainage basin upstream of each point using a DEM. This image ...
2
votes
1answer
26 views

How to merge pixel values to the nearest maximum value based on area in a classified raster?

We have a raster image with 9 discrete values. Generated the image using SAGA's Terrain Analysis -> Morphometry -> TPI classification technique. Now, like to merge pixels which occupy certain area (...