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
85 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 ...
4
votes
1answer
211 views

Why are my calls to SAGA routines in QGIS not working cross platform?

The ability to write and run cross platform scripts for QGIS using python is OUTSTANDING! However, when I try to run the SAGA:MERGESHAPESLAYERS algorithm from a python script it works fine in windows ...
1
vote
1answer
83 views

Exporting 16 bit single-band to 8 bit in SAGA

Is there any possibility exporting 16 bit single-bands to 8 bit like in qgis (gdal_translate)? Additionally in SAGA there is no option to save raster with rendering, right?
1
vote
0answers
122 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 ...
2
votes
2answers
644 views

Exporting 16 bit single-band to 8 bit in SAGA/QGIS

Everytime with every function (e.g convert data storage type or gdal-translat -ot Byte) the output is a completely white map with a black border. only the "save as" export works, but the TIFF also ...
5
votes
4answers
344 views

Create a rectangular buffer from point shapefile using QGIS/GRASS/SAGA GIS/R

I have a points shapefile and I want to create a rectangular buffer (22 x 16 km) around each point. My goal is to create a 16x22 km grid where each of the points is the centroid of the grid. Seed the ...
1
vote
0answers
16 views

Calculation of RMS between two grids [duplicate]

I want to calculate the RMSE of two grids based on their z-value: a calculated and a reference grid. I do have the statistics: Cells, Range, Min, Max, Sum, Mean, Variance, St.dev. How could I solve ...
3
votes
1answer
93 views

Underwater terrain modeling

My task is to model the surface of a lake bed, calculate volume of it and visualize it as 3D a surface. I have acquired depth measurements in a small lake using echosounder. The precision should be ...
0
votes
1answer
825 views

QGIS Processing error with SAGA, “output layer could not be open”

QGIS 2.4.0 SAGA GIS 2.0.8 DESCRIPTION ERROR when processing with SAGA. I used the "Shapes to Grid" function. The error given: "Oooops! The following output layers could not be open". This error ...
6
votes
1answer
331 views

Interactively determining upslope and downslope areas on DEM?

I know SAGA GIS can be used to interactively generate maps of upslope and downslope areas for a cell within a DEM, but the output is pretty ugly. An upslope area is defined as all cells (for a ...
4
votes
1answer
144 views

What are definitions of watershed segmentation, local maxima, variable window search, regarding LiDAR for vegetation?

I am not familiar about Lidar. I want to measure trees height and number of trees. I guess, watershed = to locate the trees, local maxima = to measure trees height. I used these methods in SAGA GIS. ...
0
votes
1answer
90 views

removing spurious lines in raster before or after vector conversion?

I'm looking for a feature/function in either python opencv/ndimage/gdal/etc. or qgis/saga/grass that will help clean up a skeletonized image that I'd like to vectorize into a shapefile of ...
1
vote
1answer
74 views

Rasterizing vectors in SAGA via saga_cmd - how to set the exact cellsize, extent (basicly grid system) based on other grid?

I'm doing some batch analysis using SAGA's saga_cmd. Basicaly I have a lot of grids and shapes (mainly generated in SAGA by vectorization of raster classifiaction results). Now I'm trying to make ...
3
votes
1answer
340 views

How to convert LAS file to ASCII for DSM in SAGA GIS? [duplicate]

I want to count trees in SAGA GIS and when I try to follow the steps in dominoc925.blogspot.com, there was no problem with asci file (i have converted las file (dem)) but there was a problem with dsm ...
4
votes
4answers
396 views

Fast and robust open source portable script or tool for interpolation - triangulation or similar

I am looking for some fast and robust open source interpolation library/script/tool. The goal is to re-interpolate relatively big (1M+ points) unstructured (xyz) grids into high resolution cartesian ...
2
votes
0answers
36 views

Can't run SAGA or GRASS commands from QGIS processing toolbox [duplicate]

I can't run anything from this toolbox. I tried running SAGA dissolve polygons and got the following error : Oooops! The following output layers could not be open Dissolved Polygons: ...
2
votes
0answers
247 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: ...
3
votes
1answer
466 views

SAGA raster calculator, ifelse command syntax problem?

I am trying to get the saga raster calculator in QGIS to spit out all values of a raster that are inferior to 10, and make all other values zero. I think the syntax is correct but I keep getting the ...
1
vote
1answer
105 views

Problem with batch mode Saga Raster Calculator

I have to do a couple of raster multiplications for which the batch mode would save me a lot of time. But the only thing I get are rasters that contain nothing but nan values. If I multiply the ...
1
vote
0answers
24 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 ...
1
vote
1answer
265 views

(R)SAGA: saga_cmd 2.1.0 error? inconsistency?

frequently I am using (R)SAGA, but after SAGA became >2.1.0 the R package is no longer working. The last update for RSAGA was 07/2013. Thus I downgraded SAGA to 2.1.0 (first try was skipping the ppa ...
4
votes
3answers
372 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) ...
4
votes
2answers
324 views

What is the source of horizontal and vertical striping in USGS DEMs?

When processing 30m and 10m DEM data downloaded through the National Map Viewer from the National Elevation Dataset, we noticed horizontal and vertical striping not only in the produced results, but ...
2
votes
1answer
403 views

Negative Topographic Index Values

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 ...
4
votes
1answer
358 views

Topographic Index - Why is upslope contributing area divided by downslope contour width and not upslope contour width?

In the Topographic Index calculation, a is the upslope contributing area per unit contour length. Is the "unit contour length" calculated from examining the contour widths of the downslope cells that ...
0
votes
1answer
64 views

How can I use polygon grid to export raster [duplicate]

I have a polygon grid which consists of 100 square polygons. For each square I need to export the raster overlay. I have ArcGIS 10.0, FME 2014, Saga-GIS. Is there a suitable tool for this or do I need ...
1
vote
1answer
189 views

How to do supervised image classification in saga with the help of R script or Python script

I am using Ubuntu 12.04 and want to do image classification in SAGA. SAGA has numerous classification algorithms which is not present in GRASS and QGIS. I am new to SAGA, but more accustomed to work ...
1
vote
1answer
461 views

catchment area using SAGA and Arcgis 10.2

I would like to calculate catchment area. I used D8 algorithm and running in both arcgis 10.2 and SAGA GIS 2.1.2. However, the results from two software are different. The lowest value of catchment ...
0
votes
0answers
51 views

Error SAGA algorithms in Modeller QGIS 2.2

I am using QGIS Modeller and I try to use SAGA algorithms but it doesn't work. GRASS algorithms work just fine but SAGA doesn't. I am not sure if I have to configurate something. What is worng?
0
votes
1answer
305 views

Is it possible to use polygons to create heatmaps?

I hope I can explain my question clearly, so here it goes: I've been fiddling around with heatmaps on QGIS for a few days, but came across a small obstacle on my way. I have a dataset comprised of ...
3
votes
2answers
131 views

Is it possible to highlight water steam sources on Landsat 7 image?

I am trying whether it is possible to view hot steam sources like power plant cooling towers and resulting cloud using satellite images. I was advised to try Landsat (needed free data for initial ...
0
votes
0answers
86 views

Software/scripts to calculate Frontal Area Index (λF)?

Maybe you know some software/scripts to calculate Frontal Area Index (λF)? This article (page 2) describes that index. For now I have not found any software or script that can calculate that (even ...
1
vote
0answers
481 views

Error when kriging in SAGA: grid file could not be opened

I have a point and a polygon vector shape (shapes) which I want to interpolate by using the saga tool "Ordinary Kriging". I always get the following error message: Oooops! The following output ...
3
votes
2answers
285 views

Select polygons that do not intersect any other polygon using QGIS, GRASS, SAGA or R

I would like to select the polygons of the layer below that do not intersect with any other polygon (within the same layer). How can I do this using QGIS, GRASS, SAGA or R?
1
vote
2answers
286 views

Create a common scale for different raster layers in GRASS, SAGA or QGIS

I have a number of layers that represent the temperature variability of the water in a lake. They have been generated trough interpolation and have different values as they represent temperatures ...
1
vote
0answers
185 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 ...
1
vote
0answers
103 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?
1
vote
2answers
381 views

Missing Dependency in SAGA. Orfeo Toolbox does not work

Hej guys, I am trying to perforem segmentation from Orfeo Toolbox (QGIS last version 2.2), whenever I try to use the toolbox, I get the following message: Oooops! The following output layers could ...
1
vote
2answers
440 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 ...
5
votes
1answer
4k views

Calculating Topographic Wetness Index (choosing from different algorithms)

Topographic Wetness Index can be expressed as Ln(a/tanB) based on the idea of Beven and Kirkby (1979) where a is the spesific catchment area (a=A/L, catchment area (A)divided by contour ...
1
vote
0answers
159 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 ...
1
vote
2answers
204 views

How to show cell values of raster in ArcGIS

I would like to know if it is possible to display a raster cell value in the center of a cell with ArcGIS in the same way that SAGA-GIS does when you zoom in.
3
votes
2answers
259 views

Merging DEMs of different grid size

I'm trying to merge two grids with different cell size. One has a cell size of 10m and the other 50m. The 10m one covers a subarea of the 50m one. I know that the most accurate one is the 10m one and ...
3
votes
0answers
760 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: ...
1
vote
0answers
124 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 ...
7
votes
2answers
1k 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 ...
2
votes
2answers
279 views

Enabling SAGA in QGIS

A similiar question has been asked recently, however I have some specific queries and process I have tried which are probably better in its own thread for clarity. Hope this is ok. See link to recent ...
1
vote
1answer
352 views

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

As my title, 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 ...
2
votes
0answers
68 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 ...
1
vote
2answers
918 views

How to interpolate a point vector layer inside a boundary (polygon layer) QGIS/GRASS/SAGA?

I have a to create a heatmap of water temperatures inside a lake for which I have sample points. The map should look much like the climate maps generated by climate change models. I have the ...