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1

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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I believe you're looking for Mosaic to New Raster in the Raster toolset. It may take some fiddling depending on how well adjacent DEMs overlap/line up. If you're running into file download limits at 2GB, you may also end up running into a problem with your output raster being too large depending how many pieces you have to combine. This may require piecing ...


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Your question is far too broad to cover in the GIS.SE Q&A format. It sounds like you're at square one with little to no previous knowledge or experience. This is fine, everyone has to start somewhere. But if you really want to learn the proper methodolgy, you're going to need to do some research into all the various steps, even just to get an overview of ...


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1) First, you need to consult the r.topidx command of GRASS GIS: With GRASS GIS: The command is r.topidx input=avauffe@tests_divers output=test_topixd 2) same with QGIS The processing log ALGORITHM|Thu Jun 26 2014 ...


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I would take a step back and ask is my GPS capable of making a DEM. The answer to this question for most consumer grade units is unfortunately no, well not without quite some work before you start interpolating etc. The vertical error in GPS can be very large even with modern units. What you are measuring is also an issue, see below. "A brief examination ...


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starting from points to build a continuous surface is called spatial interpolation. You can find information about those methods on the Web. Surfaces can be represented using wo different models : raster or TIN. Most existing DEMs use the raster model, but TIN is sometimes a good alternative. As its names says, TIN are composed of irregular triangles, ...


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If I understand your question correctly you are trying to know, on your DEM profile graph, where the water retention basin starts and ends. Here's a bit of a hacked-together idea: What if you raserized your water retention basin polygon? Then, using the same "cut" that you generated your profile from the DEM, generate a profile for the rasterized basin by ...


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I have opened the file in QGIS and it shows as 1 band paletted raster with values (colors) from 0 to 255. After closer look to histogram it actually has only values from 5 to 25 - all the yellow-greenish colors - excluding value 23 which has zero representations. Also there is value 47 which is blank edge on the left of the raster. So, if you can't get ...


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.adf is part of the raster arcinfo binary grid. You can convert it using arcgis (just add to your dataframe then right click to export it. Giving a .tif extension will automatically convert to a tif file. Note that you need to have the directory with your adf files in it. EDIT : GDAL also provide this conversion if you prefer open source. The output type ...


1

All resampling methods have advantages and inconvenients. Nearest neighbours preserves the pixel values but might duplicate or remove some of them. Therefore you will probably end up with some discontinuities on your profiles (slope, etc). Cubic convolution, on the opposite will yield smooth slopes that are nice for hydrological model, but will not ...


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There may be some more clever ways to do the job but if it is just this one image I would do it manually. First take a gdalinfo report. It will show you the palette which looks like this: gdalinfo dem_raster.tif .... Band 1 Block=19374x1 Type=Byte, ColorInterp=Palette Color Table (RGB with 256 entries) 0: 0,0,0,255 1: 58,0,0,255 2: 102,0,0,255 ...



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