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6

Set environment setting extent=your DEM extent, snap raster = DEM, cell size= one for DEM. Use raster calculator expression: Con("DEM">1500,"DEM) Right click on resulting raster, Source, scroll down to see Mean


6

There is a difference, and I recommend the typology presented by Lindsay (2015) be used. Lindsay (2015) presents a typology which defines a pit as a single cell in a DEM whose elevation is below that of the surrounding cells and a depression as a region of cells which drain inwards to a pit. This is consistent with the definitions used by O'Callaghan and ...


4

You can download a European-wide DTM from the European Environmental Agency Or use other open DTMs of Germany like this As your calculations are in SI units, you should probably use a projected grid like ETRS-LAEA (EPSG:3035) which is the scientific standard in the EU. Germany-specific grids will aslo work, as well as global ones, just make sure that all ...


3

Doing this kind of processing is pretty straight-forward, but there are some tricks along the way that will determine how accurate your analysis will be. Your data will be generated from a slope raster of the area, and you usually have to build it yourself. The easiest way is to use a DEM raster to calculate the slope, so you should start with that. Step 1: ...


3

You can use the Focal statistics tool and choose your 5x5 there or create your own kernel for it. Low-Pass is quite easy as it is just the mean which can be chosen for this tool as well.


3

Yes it will, I see nothing in this process that would result in a vertical datum change.


2

This strongly depends of the data structures you have. I think some voxel reperesentation is required for the kind of diagrams you mention. Perhaps GRASS GIS is a worth a consideration: https://grass.osgeo.org/screenshots/3D/


2

What you have is a hillshade surface built from a LiDAR point cloud. According to ESRI: A hillshade is a grayscale 3D representation of the surface, with the sun's relative position taken into account for shading the image. So each pixel of your .tif raster has an hypothetical illumination value given a reference position of the sun. What you want is ...


2

The gdal command line is great for this kind of thing. Using an ASTGTM DEM file, with heights in metres, to generate a shapefile with 20 foot contours (6.096m): gdal_contour -a elev -i 6.096 astdem.tif astdem.shp -a elev: create a field called 'elev' with the contour height in metres; -i 6.096: create contours at 6.096m intervals (20 feet); astdem.tif - ...


2

I understand you'd like to design a route between 2 points in the mountains with slope being a constraint. The solution I use is neither quick or easy. Place equidistant points over dem. Connect them by lines, using triangulation. Calculate length and slope for each and assign cost of travel through it using both values. Calculate least cost path between ...


2

To put things clear, I assume that you want to compute the area which responds to the following conditions: located inside your DEM altitude interval located inside your vector boundaries located where your second raster (let's call it raster2) has values other than "nodata" (this is the unclear part of your post, feel free to correct me if I ...


2

--- gdal --- use gdal_contour function. documentation here ---- ArcGIS version----- posted before the software was specified Assuming you are using ArcGIS: 1. Convert the GeoTiff into ESRI GRID (esri raster format) using raster to other formats function, or simply import it in arcGIS and use save (export data) and save it as ESRI GRID. 2. use the Contour ...


1

This aspect come from TIN interpolation. You can try others interpolation methods. You'll find more algorithms in the processing toolbox, especially the SAGA tools.


1

What recourse do I have in this situation? Acquire/integrate data with finer resolution. Can the 10m DEM be re-sampled perhaps to more accurately reflect the actual landscape? No, it can't. At least without inputting additional data. Should field surveys be employed in addition to re-sampling? It is an alternative. Alternatively, are you ...


1

You will have to dump that tiff file (or whatever) into a <canvas> and read the values of whatever pixels you want. Be aware of cross-origin issues. Do read: https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Tutorial/Using_images https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Tutorial/Pixel_manipulation_with_canvas


1

Try this tool box. It has a tool that allows you to create filled contours, from which you can easily work out areas.


1

If you do have the 3D Analyst extension, it should work this way: Use the tool 'Interpolate Shape'. This will add a Z coordinate information to your points. Use tool tool 'Add XY coordinates'; this will add the XY and also Z coordinates of each point into the attribute table of the shape.


1

I have done all modules of grass7.0.3 works but nviz7 NO! Could be a PATH problems. The nviz7 command isn't under grass7.0.3 dir!? I found nvzi7.py in the ./qgis/python/plugins/processing/algs/grass7/nviz7.py dir but how could by call!?



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