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++.

learn more… | top users | synonyms

1
vote
0answers
11 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, ...
-1
votes
0answers
9 views

Slope Length in SAGA [on hold]

I'm using SAGA GIS software to compute slope length of SRTM DEM. whenever I try to execute the tool, I receive an error: could not initialize data objects How can I resolve this?
1
vote
0answers
23 views

Importing TIFF to SAGA

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 ...
1
vote
1answer
41 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 ...
1
vote
1answer
26 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?
0
votes
0answers
15 views

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 ...
2
votes
1answer
29 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 ...
4
votes
1answer
105 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 ...
0
votes
0answers
15 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 = ...
2
votes
1answer
60 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. ...
3
votes
0answers
33 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, ...
5
votes
3answers
77 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 ...
4
votes
0answers
37 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, ...
30
votes
4answers
553 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 ...
3
votes
2answers
142 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 ...
3
votes
1answer
46 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__
2
votes
1answer
150 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.
1
vote
1answer
345 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 ...
3
votes
0answers
39 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 ...
1
vote
1answer
58 views

QGIS 2.12 Lyon - SAGA dissolve tool keep only one column of data

I have installed QGIS 2.12 Lyon and I need to dissolve multiple polygons according to one column in the dbf file (my layer is a shape file). I have used SAGA "Polygon dissolve by attribute" algorithm ...
1
vote
1answer
129 views

Saga tools missing in QGIS [closed]

First things first! I am using Ubuntu Mate on 15.04. I installed Qgis and SAGA via the http://ppa.launchpad.net/ubuntugis/ubuntugis-unstable/ubuntu packages. So I use QGIS 2.12 and SAGA 2.1.4. I ...
2
votes
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 ...
2
votes
0answers
49 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 ...
1
vote
0answers
28 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 ...
1
vote
0answers
45 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 ...
1
vote
0answers
62 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 ...
0
votes
0answers
7 views

Sky View Factor of building roofs => Vector algorithm [duplicate]

I'm currently working on a project in which I'm trying to assess the SkyViewFactor of a given roof using building vector data. I've already managed to build a process based on vector rasterization ...
1
vote
0answers
89 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. ...
1
vote
1answer
50 views

osgeo4w not installing processing tools in QGIS toobox. [duplicate]

I have uninstalled and reinstalled QGIS several times from the OSGeo4W application. I have done this with no problem on several other times, but now I cannot get the tools to load. Most of the help ...
0
votes
0answers
52 views

NDVI Workflow Problems, Red Channel Seems High Causing Low NDVI value?

I did some searching but nothing came up around this. I'm trying to verify a workflow from images to an NDVI to verify I have a basic workflow correct. Process images example dataset through ...
1
vote
2answers
120 views

How to sum values of overlapped pixels in thousands of rasters layers and clip it using a polygon in QGIS?

I have a lot of rasters files (more than 6000), each one represents the presence and absence of a species (1 for presence and NoData for absence). The set of rasters covers the whole Latin America ...
0
votes
0answers
186 views

SAGA version with QGIS 2.10

I want to know which version of SAGA is used with QGIS 2.10. I developed a standalone application which uses QGIS inside. I have problems using SAGA algorithms. SAGA is well installed but I found that ...
2
votes
0answers
80 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 ...
0
votes
2answers
275 views

Does Processing plugin v2.10.1 not recognise SAGA?

Version 2.9.3 of the Processing plugin works fine, I can run the SAGA tools successfully. Updating the Processing plugin to version 2.10.1 results in SAGA disappearing entirely from the toolbox. The ...
2
votes
1answer
212 views

SAGA tool 'Relative Heights and Slope Positions' - What do results tell me?

I am currently trying to get in morphometry, using the SRTM 30m DEM. I was recommended to test the SAGA mudule 'Relative Heights and Slope Positions' ...
1
vote
0answers
56 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 ...
3
votes
0answers
75 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 ...
1
vote
2answers
195 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 ...
1
vote
0answers
39 views

Hydrology Analysis via SAGA - what is the unit? [closed]

I did a couple of analysis via SAGA about an area in Iceland...I've never worked with SAGA before, could anyone tell me what Units the numbers in the legends for "Catchment Area Recursive" and ...
0
votes
0answers
90 views

From DEM to Topographic Wetness Index in SAGA GIS

I have DEM in GeoTIFF format and I wish to calculate Topographic Wetness Index in SAGA GIS. TWI tool in SAGA GIS expects that user provides two values - 'slope' and 'catchment area'. Since there's ...
1
vote
0answers
62 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 ...
1
vote
0answers
58 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 ...
1
vote
1answer
389 views

SAGA algorithms don't work in QGIS 2.8

when I have installed recently QGIS 2.8 and, since then, SAGA algorithms don't work. Apparently, the algorithm runs well (any error is showed while it is executing the algorithm), however, there is ...
0
votes
2answers
264 views

how to add multiple grids in SAGA gis

Here is the "big" problem: my Digital elevation model is divided in a lot of pieces (single files .xyz). In order to build a mosaic of them I need to import them all. With SAGA I can import them ...
1
vote
0answers
93 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) ...
4
votes
0answers
102 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.
1
vote
0answers
99 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 ...
2
votes
1answer
96 views

View feature space for multi-band files

I am trying to plot a feature space (scatter plot) for some SPOT images in QGIS 2.8.1. I know a histogram is available in the file properties, but I want to plot eg. Band 1 vs Band 2 to see the ...
0
votes
0answers
23 views

Generating a plot by varying the buffer around each point

I want to create a plot like this: Basically, I have a bunch of points (properties), some of which have (and some of which don't) have Property X (e.g., a fence). I want to find out how the ...
1
vote
0answers
72 views

Is there a list of Open Source tool alternatives for ArcGIS tools? [duplicate]

Is there any place one can find a list of ArcGIS alternative or near-alternative tools found in (any of) the open source softwares? I am not looking for software but individual tools found in the ...