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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1answer
23 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
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0answers
17 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
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0answers
66 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 ...
1
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1answer
55 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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0answers
15 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 ...
3
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1answer
74 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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0answers
34 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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0answers
24 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 ...
3
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3answers
231 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. ...
4
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1answer
96 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
44 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.
1
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1answer
49 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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0answers
34 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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0answers
31 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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0answers
20 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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0answers
33 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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0answers
16 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 ...
2
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0answers
34 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 ...
1
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1answer
99 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 ...
1
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1answer
24 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 ...
0
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1answer
60 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
14 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 ...
3
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0answers
57 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 ...
2
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0answers
29 views

How to remove spikes from grid in SAGA GIS?

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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0answers
82 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
33 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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0answers
25 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
121 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 ...
2
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0answers
33 views

Batch raster calculation of slope and aspect in SAGA

I am relatively new to the SAGA software, I have only used it for small amouns of data, and for basic calculations. My data is obtained by mapping certain areas in GoogleEarth, then, overlaying the ...
2
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1answer
197 views

Orfeo tool box (OTB) in Ubuntu 14.04 and SAGA incompatibility (gdal versions)

I need to test segmentation of a 12000 x 12000 pixels scene. I successfully compiled OTB in Ubuntu 14.04 and ran the process. But when I tried to start SAGA, I got a startup error. I found that gdal ...
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0answers
132 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 ...
1
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1answer
50 views

best algorithm to trace stream network in flat areas

i want to ask you what method do you suggest me for to trace stream network in flat areas and please explain me how to deal with the previous preapration of the DEM regards many thanks
0
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0answers
27 views

saga:slopeaspect curvature

I'm using windows 7 on 64 bit and using Qgis 2.6.0.I'm trying to process some Tifs from the console using the processing toolbox and saga:slopeaspectcurvature. This is pretty much how my code looks ...
1
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3answers
50 views

How to narrow raster features to single cell width?

Are there any tools or existing workflow which convert raster features (such as roads, rivers, electric lines etc.) which are (or can be) multiple cells wide to a single cell widht (i.e, center line). ...
0
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1answer
73 views

SAGA Cluster Analysis for grids projection issue

I am having an issue with the SAGA cluster analysis for grids tool within QGIS 2.4. I am actually taking this as an online class through Del Mar and we are going over supervised and unsupervised ...
2
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2answers
75 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 ...
3
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1answer
48 views

How to export data from saga or tas into excel?

I want to derive terrain attributes from DEM with saga and whiteBox GAT (SAT). I have problem in exporting data into excel. would you help me?
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0answers
100 views

Issues with reclassify for QGIS Saga Reclassify Grid Values tool

I am trying to reclassify a raster using the Saga Reclassify grid values tool in the QGIS Processing Toolbox, but am getting an unexpected entirely black raster. I have verified my original points and ...
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0answers
76 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
160 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
73 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?
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0answers
87 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
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2answers
460 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
278 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 ...
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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
81 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
522 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
275 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
102 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
73 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 ...