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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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 ...
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21 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 ...
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1answer
168 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 ...
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1answer
45 views

How to remove spikes from grid in SAGA GIS? [duplicate]

I tried to get a grid by interpolating LAS file using Ordinary Kriging. But the product grid has many pixels which values strongly stands out from average surface - I mean one pixel sinks nad spikes. ...
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28 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 ...
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2answers
130 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 ...
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1answer
149 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
757 views

Calculating longest flow path and avg. slopes for catchments with qgis?

I am a hydrologist and their are 2 important pieces of information I need for modeling. I need to know the longest flow path for each sub catchment in my area of interest and I need to know the ...
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1answer
69 views

Can't import libraries to rsaga

I get this error when I'm trying to import a raster to RSAGA: > rsaga.import.gdal(paste(rast_name, ".tif", sep=""),"RASTER", env= my_env) Module 'GDAL: Import Raster' not found in SAGA library ...
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58 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) ...
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3answers
1k views

QGIS 2.0.1 Dufour on Windows 8 64-bit: Processing toolbox always produces error saying output layers could not be opened

I have tried to use the Processing Toolbox in QGIS 2.0.1 a couple of times now (using SAGA and OTB) and in both cases the processing tools always return an error along these lines: "Problem loading ...
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4answers
349 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 ...
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6answers
1k views

How to integrate SAGA Python Modules into ArcGIS Desktop?

I have been having a look at SAGA (http://www.saga-gis.org/en/index.html) and it seems to have some nice tools for geoprocessing. I was wondering if anyone out there has had any luck bringing SAGA ...
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40 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.
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54 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 ...
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450 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 ...
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3answers
101 views

Find coordinates of given raster value

I would like to get the coordinates of a raster cell with a given value. I suppose many cells can take the same value, in which case several coordinates should be returned. In my first problem I'm ...
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1answer
48 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 ...
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19 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 ...
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0answers
69 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 ...
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1answer
98 views

QGIS SAGA Raster Calculator

I am using SAGA --> Grid Calculus --> Raster Calculator on QGIS version 2.6. The formula I am using is: ifelse(gt(a,0), (a), b) where a is my layer with values in a greater extent than that of b. ...
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1answer
132 views

Unsupervised classification in QGIS

I was trying to learn unsupervised classification in QGIS 2.6 following the tutorial video: https://www.youtube.com/watch?v=mI80eENtWSE When trying myself, clicked Run during the process it shows the ...
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1answer
240 views

Creating New Modules in Saga GIS

I have recently started development with SAGA and have run into some difficulties. I have checked out the svn code base and have successfully compiled in VS-10 (except the project ViGrA). Now I just ...
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29 views

SAGA Raster Calculator, ifelse doesn't return specified value exactly

First time caller, long time listener.... I am using the SAGA Raster Calculator in QGIS 2.6 to change NaN values to zero and that part is working great, however the specified 'if' value is being ...
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8answers
7k views

Splitting shapefile into separate shapefiles for each feature using QGIS/GDAL/SAGA?

I have a polyline shapefile with about 20 kinds of roads. I would like to know how can I create automatically a vector file for each one. I am aware of how to do it using ArcGIS for Desktop - see ...
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3answers
409 views

SAGA installation in QGIS 2.8 on debian linux

I install QGIS 2.8 in debian (linux) through nightly jessie (qgis testing) and I see that SAGA is not in processing toolbox, so I install saga gis software but still it doesn't appear in processing. ...
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2answers
297 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 ...
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27 views

How to load “soil types” in QGis?

I want to show soil transmissivity per pixel. Thus, I determine water holding capacity of each pixel (ignored other effective parameters). Respectively, I wonder, What is the soil data format and How ...
4
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1answer
135 views

How to calculate “water accumulated in each cell” using QGis?

I create channel network and catchment area from a DEM with SAGA GIS. I know that flow is starting from a cell to an other cell. Firstly, a cell is filled with water and then it is starting to flow ...
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2answers
47 views

Representation of precipitation data

I have an excel sheet of precipitation data of each month of some districts. I have also the shapefiles of these districts. How can I represent this data in these shapefiles.
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45 views

How to decide when flood started depending on the rainfall data?

I created a raster with the point values (mm) of rainfall data by interpolation in the raster menu. So I have a raster rainfall data and a DEM. With this rainfall data and a DEM corresponding to ...
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1answer
99 views

setting SAGA folder for QGIS with OS X macports install

I am trying to get the toolbox to work in QGIS 2.6, but I keep getting an error message that SAGA is not properly configured. After much digging, I finally found I can set the SAGA folder in ...
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50 views

SAGA GIS - raster image from Civil 3D

I am a new user of SAGA GIS software. I need to interface the Civil 3D 2015 and Hec Ras software in order to create a flooding map. In order to put in communication the two softwares, I have to use ...
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184 views

QGIS SAGA Channel network error: Input layers do not have the same grid extent

I am trying to follow along with this exercise using my own DEM. I have done the first step, creating the catchment area, with no trouble. When I try to run the Channel network algorithm, however, I ...
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23 views

What is the background processing of rainfall thresholding?

I want to create a flood map using Quantum GIS. First of all I create catchment area (flow accumulation). Then, I delineate a Channel Network by applying a threshold to flow accumulation. So I want to ...
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1answer
112 views

saga_gui.exe identified as malware by antivirus when downloaded from OSGeo4W

I downloaded QGIS 2.6.1-2 (Brighton) yesterday from OSGeo4W-setup-x86.exe using the advanced installation option on a machine running on windows 7 professional. The download worked Ok except for saga ...
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0answers
56 views

QGIS 2.6 SAGA Processing Algorithm, “Add grid values to shapes”, produces NULL Values

I'm using QGIS 2.6 Brighton on Windows with SAGA 2.0.8 installed using OSGeo4W. I have the same versions installed on OSX as well which is not having this problem. On Windows, I'm trying to extract ...
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35 views

How to calculate the Vertical Distance to Channel Network in ArcGis?

In Saga there is the tool "Vertical Distance to Channel Network". Is there a way to produce the same data in ArcGIs? With con("flowacc" > xx, 1) I was able to create the Channel Network. I am ...
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3answers
1k views

Generating raster from isolines using SAGA or ArcGIS?

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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0answers
49 views

How to read .asc format DEMs that have headers with #comments

I have around twenty 2 GB DEMs (xyz) in .asc format. The header has 13 lines of metadata, and then the basic data in three columns # # The DTM grid had lower left (southwest) corner coords: # X ...
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1answer
38 views

Saga:processing resample extent in python editor QGIS

I would like to resample many geotiff layers to another geotiff layer's extent and pixel size. For this I would like to use the QGIS python console (editor). When I run my script it raises the ...
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1answer
72 views

Fill polygons via data-defined pie charts

I am trying to summarize my polygons by each's distribution of some variable. To couch the discussion, let's say we wanted to summarize the demographics of each county (of a small state) by it's ...
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0answers
19 views

Unable to execute the algorithm using SAGA LS factor

I tryed to calculate the LS Factor at SAGA, using a slope raster and the area raster, both at the same EPSG, and the error:Unable to execute the algorithm the error means something with the coordinate ...
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61 views

QGIS algorithms do not work on copies of shapefiles?

I'm using QGIS 2.6.0. I'm trying to run various algorithms such as "SAGA/Shapes-points/remove duplicates" & "SAGA/Shapes-Grid/Add grid values to points" through the sextant toolbox. When I run ...
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93 views

Problems using the SAGA in processing framework with qgis 2.6.1 (ubuntu) [closed]

I've got problems using saga in the processing framework within qgis 2.6.1 and SAGA 2.1.4 To solve this problem I was obliged to correct the line 352 of the python file ...
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0answers
42 views

What does the b-spline-interpolation-algorithm actually do?

Right now, it is just a Blackbox-way to interpolate a DEM. I know to some extent how for example the nearest-neighbour-method works, but I have no idea about b-spline. It would help to understand the ...
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3answers
2k views

How to set all pixels with value <= 0 to “nodata” in DEM raster?

I have a DEM raster with pixel values between about 3000 and -0.0003. I need to set all pixel with a value of 0 and smaler (<=0) to "nodata" (for later raster calculations and to reduce the ...
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32 views

Join polygons by plurality overlap

I'm trying to join two layers-- One is census tracts in Michigan; The other is school districts. Because there is no nesting in either direction (districts in multiple tracts and vice versa), I'm ...
3
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0answers
158 views

SAGA is not working within sextante (QGIS processing installed in Ubuntu)

Recently i decided to start working in Ubuntu (version 14.04). My first step was to add the ubuntugis-unestable repository, and then proceed to install SAGA, GRASS, OTB, QGIS and the bindings between ...
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1answer
251 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 ...