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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Image segmentation in SAGA Tutorials

I am searching for tutorials for the Image Segmentation modules of SAGA (version 2.0.8). The official wiki from the software doesn't contain any info on this modules, same thing happens in the ...
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54 views

SEXTANTE Saga-grid normalisation and KBS

I tried to use the saga tool grid normalisation. The result is ok but the KBS has changed. Is this an error?
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1answer
701 views

How to get SAGA working with QGIS Sextante?

I just created my account on this forum to find an answer to a stupid (?) problem I can't deal with. First, let's precise I just (some months ago) learned on my own what GIS was, and gave it a try ...
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6answers
527 views

Tool/Algorithm for generalizing OSM-Files for printing maps

Is there a tool or algorithm to (topological) generalizes OSM-shapes? I would like to build a printable map in different scales. In the image below you can see the same divided road (yellow) at ...
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1answer
209 views

SAGA GIS ----> need to export shapefiles to SVG

I am trying to export three shapefiles to svg files but the problem I could not make these shapefiles polygon to black outlines to be export to svg files. How do I do that ? I tried to run that in ...
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2answers
585 views

How do you read GeoTiff-file in SAGA GIS Program?

I'm very new with all GIS-stuff and I got advice that SAGA GIS would be a good program to start with. I would like to read a GeoTiff-file in SAGA, but I can't find an "import file"-function x) Any ...
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1answer
159 views

How to open a .k format (I think it is made with IDRISI product) with open source software

I just received a .k file which I know it was made with a IDRISI software (I do not know which). I searched the web and I did not find many information on this format apart for a very essential page ...
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0answers
402 views

QGis Grid statistics for polygons error - Module caused access violation!

I'm trying to calculate statistics for a raster layer using an overlaying polygon layer, I'm using SAGA "Grid Statistics for polygons" function, but it returns an error, sadly.. So in the sextante log ...
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2answers
1k views

saga & grass configuration in sextante (ubuntu)

I have some trouble in running saga and grass algorithms in sextante. When I double click it appears a pop-up saying: Missing dependency.This algorithm cannot be run :-( This algorithm requires SAGA ...
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1answer
923 views

Topographic Wetness Index

Is there any option to SAGA to calculate the Topographic Wetness Index ? I have a big area and I tried many times with SAGA, the last time I thought the results was ok (before SAGA would crash or give ...
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1answer
643 views

How to fix erros loading result layers from SAGA functions in Sextante?

Using QGIS 1.8.0 and SAGA When trying to use the IDW function from Sextante SAGA 2.1.0 64bit, I get the following error: Could not load layer: C:/test.tif. This error seems mysterious to me, any ...
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2answers
365 views

SAGA, GRASS Raster values to null

I want to make the cells which values "1" to null in QGIS with Grass or Saga tools (exactly Saga).
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1answer
125 views

Differences in raster extents in gdalinfo, SAGA & Quantum after resampling

I recently resampled a raster file using SAGA's Resampling module. The aim was to widen the extent of the new raster to two decimal places, where the original raster has three decimal places. The ...
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2answers
84 views

How to align directions of connected lines?

I have a vector line made of different pieces of lines with different directions. I merged the lines to one. But this merged line still have different direction in its "invisible" parts. I want to ...
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1answer
132 views

Determining Pixel-by-pixel Catchments in ArcHydro

I used ArcHYDRO to prepare HydroDEM (5m) without sinks, Flow direction (FDR) raster, flow accumulation raster (FAC). As I understand FAC, value of pixel shows number of pixels that contribute to this ...
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1answer
311 views

QGIS Sextante Python UnicodeEncodeError

I have some issues with Quantum Gis 1.8. When I try to use shapes to grid (sextante-saga tool) I get the following error (comes up when I try to define the new grid file name): Fehler bei der ...
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1answer
614 views

QGIS, Euclidean distance analysis [duplicate]

i wanna generate euclodian distance map for my road data. I 'll use it for multi criteria analysis. I can get it by using Arcgis Euclodian Distance tool but i wanna generate it in QGIS environment. I ...
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1answer
48 views

GRID TO TXT in saga

i have a problem in SAGA. I want to export several raster files to a .txt file. It means integration raster files to a .txt file. Can I do this in SAGA. Please explain? Thanks
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2answers
1k views

how to convert grid from Saga gis to have raster in Arcgis?

i am new in Saga Gis, i created grid- LS factor (from Rusle equation for erosis) in Saga gis and now i need to "put" it to Arcgis. How can i do this? I tried a lot of possibilities and none of them ...
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1answer
254 views

How can I avoid reprojection gaps when merging DEM rasters?

I have two raster DEMs in same resolution I want to bring together. I was using the merge-function in SAGA, GRASS and QGIS but I always get the following result: What do I need? Where could the ...
3
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1answer
799 views

Hydrologic analysis with sextante-saga in qgis

(rough translation): Hi, I want to do hydrologic analysis of a DEM with sextante-saga in qgis. I found the plugin and the needed algorithms in SAGA, enabled them in the sextante toolbox, but when I ...
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2answers
426 views

SAGA-GIS Produces different results in command line than GUI

I have been working on a lidar processing workflow using SAGA-GIS. I determined my workflow on a single tile in the SAGA GUI and now I need to batch the operations on 100 more tiles. I wrote a batch ...
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1answer
264 views

Getting SAGA-GIS Python Bindings without compiling from source

I am very new to SAGA-GIS, but I recently developed a workflow using SAGA for processing LiDAR data. Now I need to batch the process using Python. I installed SAGA from the Windows installer and I ...
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1answer
418 views

Generalize large polygon-file

I have a large polygone file with landuse information (6 classes). Its vectorised from a raster classification so the polygons are all angular. Any of my tries to generalize with v.generalize (sneaks, ...
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2answers
631 views

gdal doesn´t support my *xyz file

I have just exported a tif DEM to XYZ format with SAGA GIS. When I check this with gdalinfo it states that the format is unsupported? Seeing as I converted this with saga gis which used gdal I find ...
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2answers
149 views

Is it possible to import SAGA colour styles in QGIS?

iam still using QGIS and SAGA independently in my productive use (despite the excellent SEXTANTE toolbox, which is sometimes a little buggy). SAGA has some very nice default styles and i am wondering ...
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1answer
3k views

Calculate Topographic wetness index in SAGA

i am currently working on a project which involves the quantification of the wetness in certain areas. However it produces quite different results from what i expected. I'll describe the steps i have ...
3
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1answer
163 views

Convex Hull in SAGA Gis

How does one go about creating a convex hull from a set of points in SAGA GIS? I read that this is possible in QGIS, but I prefer SAGA and would like to see if it is possible. Furthermore, if it is ...
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2answers
1k views

How to implement viewshed calculation?

I'm looking for a way to implement visibility (aka viewshed). I found a previous GIS SE question that suggested a few GIS applications (not what I need - I'm trying to embed the calculations), and ...
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2answers
2k views

How to compare two DEMs and show their difference?

I want to compare my DEMs (ASTER GDEM2 and SRTM4.1). I know, that the GDEM has some extreme "holes" with totaly wrong elevations (I found 3 of them in my working area). Now I need to know, if there ...
5
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1answer
3k views

How to configure QGIS Sextante to use SAGA?

I have been trying to set up SAGA to work using Sextante in QGIS. I have followed the instructions to configure SAGA in Sextante, with the following input in the path for the SAGA folder C:\Program ...
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2answers
2k views

How to smooth large vector polygons from Raster

I have a landuse classification raster file (6 classes) of a large area. But I need it in vector polygons so I vectorised it. No problem so far, but the result is - of course - that every pixel is ...
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5answers
1k views

How to generalize and vectorize a LandUseClassification raster file?

I want to vectorize that rasterfile with its 6 landuse classes. The classification is very noisy and have to be generalized before. The result should be a polygone vector file. I use SAGA, (GRASS) ...
4
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1answer
276 views

Stripes in Landsat-image after topographic correction (SAGA)

I got stripes in my topographic corrected Landsat images (see second image below). I used SAGA GIS 2.0.8 at xubuntu 12.04 Image and DEM are in the same projection, tried it with EPSG:32636 and ...
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3answers
938 views

Generate raster from isolines

I have a vector dataset of mean annual precipitation polylines, and I would like to generate a raster from them. I'm not sure the best way to go about it. ArcGIS has the Polyline to Raster tool but ...
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3answers
561 views

Topographic correction (for land use classification) with SAGA or GRASS

Is there a module in GRASS or SAGA (or a alternative open program) to do a topographic correction of a landsat image to enhance the land use classification? Thanks! Martin
5
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1answer
2k views

How to perform Ordinary Kriging in SAGA via QGIS SEXTANTE Plug-in?

I'm trying to learn how to apply the kriging analysis in QGIS using the SEXTANTE plug-in and SAGA tools. It appears that I have my SEXTANTE and SAGA folders configured properly according to the user ...
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2answers
1k views

Is it possible to manually correct a raster DEM (OpenSource)?

Is it possible, to correct a raster DEM by changeing the raster-cell-values manually, like by "painting"? My DEM (ASTER) have one small error where the elevation is about 300m below the actual ...
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2answers
655 views

Convert classified raster map back into vector classes

I have this map (have whole country, this is just a sample, original map also contains color symbology for the value classes) and need to attach the values from it to points. I have no problem to ...
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2answers
837 views

Interpolation of contours (from one “main-contour-shapefile”)

I calculated, that the best and smalest possible äquidistance (equidistant) for my map is 30m. After I generlized my DHM, I extracted contours of a intervall of 30m and smoothed them. Now I have my ...
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2answers
412 views

SAGA-GIS:Viewshed creation from SHP instead of interactively?

I am using Saga-GIS to calculate a viewshed from a single point. I can do this with the interactive module, (terrain analysis > Lighting > visibility (single point) interactive) but how do I do it ...
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2answers
919 views

SAGA GIS: How to load an .hgt file?

I want to display and work with the data from http://dds.cr.usgs.gov/srtm/version1/Eurasia/ in SAGA-GIS but am having difficulties knowing which module I should use to load the data. As far as I know ...
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4answers
869 views

How to automatically plot intermediate contours with QGIS, GRASS GIS or SAGA GIS?

I'm mapping a steep mountain range. My main contour interval is 50 m and my intermediate contour interval is 10 m. In steep areas, the interval of 10 m is too small, so I need to leave ...
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4answers
4k views

How to split a vector in equal smaller parts in QGIS or similar?

i want to divide a shapefile with many tiles into a lot of smaller tiles. I am searching for a smart solution, because manual edits are out of questions Anyone can help or know a nice function?
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4answers
6k views

How to calculate raster statistics for polygons?

how can I calculate sums, averages etc of raster-points (multi-band) per polygon of a vector-layer. I was told that this is called "zonal statistics". I tried that with QGIS first. There is a way to ...
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1answer
473 views

How to create a profile with profile points at discrete altitude intervalls, e.g. each 10 m

In both SAGA and QGIS theres a profile-from-line-function that does a nice job of creating profiles. But there's no way to control the altitude spacing. Any ideas for workflows that would allow me ...
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2answers
2k views

Efficiency of python script using SAGA and arcpy

=== SUMMARY === I have created a process to import a LAS point cloud, clip it, select the ground points and save the output as an XYZ.txt for clients to use. This uses a python based script (will ...
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1answer
322 views

Comparing GIS libraries

I am new to GIS. As a part of my research, I want to figure out among OSSIM, Saga API, Terralib and MApnik which one will best satisfy the following functionalities and why ( all for desktop GIS ...
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0answers
418 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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2answers
686 views

Altitude Above channel in GRASS 6.4

i'm fairly new to the GIS world and GRASS (come from econometric background), i would like to do some species distribution modeling using R and GRASS. So i started to read the book of Tomislav Hengl ...