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After I checked my data source and used different GIS Tools (under them 3DEM a really nice DEM Viever, that gave me the right heights), I came to the conclusion that the grayband values, that are shown by QGIS, when you drag your DEMs in it, are simply wrong and aren't the height values. Both SRTM and ASTER DEMs store (in general) their data in meter. If ...


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The description is not very thorough and it is hard to know what causes those errors, but here is something that might help. Set zero values to NoData for both rasters (use ArcMap Set Null -tool or rastercalculator). I would suggest that you convert the bathymetric file into .tif -format, so that it eliminates the conflict between the different file types ...


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From a theoretical point of view depression filling only has one solution, although there can be numerous ways of coming to that solution, which is why there are so many different depression filling algorithms. Therefore, theoretically a DEM that is filled with either the Planchon and Darboux or the Wang and Liu, or any of the other depression filling ...


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I will attempt to answer my own question - dun dun dun. I used SAGA GIS to examine the differences in filled watersheds using their Planchon and Darboux (PD) based filling tool ( and their Wang and Liu (WL) based filling tool for 6 different watersheds. (Here I only show case two sets of results - they were similar across all 6 watersheds) I say "based", ...


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Constructing lidar DEMs from unclassified point clouds with: MCC-LiDAR using the Multiscale Curvature Classification (MCC) algorithm. MCC-LIDAR is a command-line tool for processing discrete-return LIDAR data in forested environments" (Evans & Hudak, 2007). Workflow illustration (gross cloud --> ground returns classified --> bare-earth DEM): ...


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As others have suggested, reproject to something with a linear measurement. But be sure to use BILINEAR interpolation (not the default of Nearest Neighbor). This should avoid the grid-like artifacts that stem from resampling patterns (you may notice that if you do multiple reprojections and change the cell size among them, you can get the cross-hatching to ...


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There are a few posts on the possible source of the striping that are too long to copy here and post, for example https://geonet.esri.com/message/248734?sr=search&searchId=8194652f-cac8-4737-93a2-c5dccdeb29ff&searchIndex=5#248734 http://ned.usgs.gov/about.html http://www.ctmap.com/assets/pdfprojects/destripe.pdf Some of the issues are associated ...


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import arcpy import numpy mxd = arcpy.mapping.MapDocument("CURRENT") df = arcpy.mapping.ListDataFrames(mxd)[0] anExtent=df.extent raster=arcpy.GetParameterAsText(0) desc=arcpy.Describe(raster) cSize=desc.meanCellHeight nRows=int(anExtent.height/cSize)+1 nCols=int(anExtent.width/cSize)+1 myArray = ...


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The answer seems to be that r.topidx works when called through the GRASS tools, which are available after selecting and loading the GRASS plugin. It is available, but does not work (for me) when called from the Processing Toolbox. I found this confusing, because some GRASS routines do work when called from the Processing Toolbox. To use r.topidx (and ...


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Try using this, http://resources.arcgis.com/en/help/main/10.1/index.html#//0017000000m3000000 Turn the current data frame extent to a polygon via this extent = inFeature.extent extentPoly = drive + "\\NCT_GIS\\Projects\\Temp\\extentPoly.shp" # Array to hold points array = arcpy.Array() # Create the bounding box ...


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>>> myList=[3,9,15,1] >>> mX=max(myList) >>> mN=min(myList) >>> mX-mN 14


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Use Get Raster Properties, specifically the MINIMUM and MAXIMUM values. In theory, this code should make a temporary raster layer using the display extent -- although I have not tested it, and am not sure whether it will work -- and then the raster properties tool will apply to only the raster currently shown in the display. import arcpy arcpy.env.extent ...


3

the gdal driver (used by QGIS) supports eight, sixteen and thirty-two bit integer raster data types as well as 32 bit floating points for conversion to bil. based on the error message, your tiff data seems to be 64 bit (double) type, which is not supported. You could try to change the pixel depth before converting to .bil


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A solution to this is discussed on the ESRI forum here: Every planar surface has a simple formula, Jesse, in the form (something)*x + (something else)*y + (constant). In the Raster Calculator, x is $$XMap and y is $$YMap. The trick is figuring out the coefficients. Often you want to specify a plane in terms of its slope (s), aspect (a), ...


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To do this you would need a 3d Analyst and Spatial Analyst license. First, elevate your waterbody using Interpolate Shape, this will give the baseline for your elevations by attributing the polygon with the Z values from the DEM to each vertex. Build a terrain with your waterbodies as the elevation data source (perhaps buffer by a small amount and include ...


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You can't get elevation from Orthorectified photography. To get elevation data from airphotos you need special photos, hardware and software: Photos: Sterio pairs, a set of overlapping images with an accompanying file detailing the location of the aircraft at the time of capture (x,y and z). Hardware: 3d monitor, with glasses. Nowdays you can get cheap 3d ...


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It is handled by an esri geoprocessing service, which it is recommended that you update from the old service. The details page mentions plenty of good reference information.



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