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3

Please note that both methods below will export non smoothed polygones boundaries. You may have to resample your DEM file to get smoother lines or use further smoothing techniques. Step 1 : Spatial Analyst (Classification) You could use Spatial Analyst to classify your data in 2 classes : 1 = data within the boundary values (example : elevation < X ...


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f I understand correctly you only want to create polygon boundary that surrounds elevations that are below a certain value... Assuming you also have 3D analyst/ Spatial Analyst extensions, there are probably several different ways to do this. Here is the Cut/Fill Tool technique but it involves several steps: I (The Cut Fill tool but this requires raster ...


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Your main question title indicates you're looking at sea level and coastal areas. But we'll start at the bottom of your question and work backward. Consider lakes and rivers. Many of them may be significantly above sea level, even their bottoms, thus relying on elevation alone in the DEM cannot tell you if an area is water or not. Plus in a DEM large water ...


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Two ways to go about this using ArcGIS: Interpolate - makes more sense: Use the Raster to Point tool on your DEM and set the Field option to Value. You will get a layer of points for each center of pixel, with the elevation value of the pixel stored for each point. Then use the Create TIN tool and use both layers as inputs - the layer of elevation values ...


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Base on your specification, i think ESRI ASCII raster format is the most suitable format. This link explain the basic structure of ESRI ASCII format : http://resources.esri.com/help/9.3/arcgisdesktop/com/gp_toolref/spatial_analyst_tools/esri_ascii_raster_format.htm I hope you can figure out how the header and the value can match with your specification ...


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You can use the function ST_DumpAsPolygons: SELECT (ST_DumpAsPolygons(rast)).* FROM road_linestring_table,dem WHERE ST_Intersects(rast, geom); Afterwards you can rasterize the result.


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As the other replies say the statistics are likely out of date. If you prefer using ArcGIS try the Calculate Statistics tool in the Data Management toolbox. This should update the statistics for you.


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I imported my raster file to PostGIS and I used this function to make vectorization of my raster. I used this query SELECT (ST_DumpAsPolygons(rast)).geom,(ST_DumpAsPolygons(rast)).val from my_raster


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As whuber mentioned, often statistics found in the raster properties are sometimes approximate or are out-of-date. They are predetermined properties that can be misleading to the actual raster values. Calculated your own min / max values from 100% of the actual data using NumPy arrays. See Working with NumPy in ArcGIS, and RasterToNumPyArray (arcpy). E.g.: ...


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If you want to create 10 m contour interval, so you have to find a primary data ( Your DEM's data) which has spatial resolution 10 meter or smaller like InSAR. Your can't create an interval contour smaller then it's DEM resolution because when you generate the contour using ArcGIS, the algorithm will try to find the nearest neighborhood between spot height ...


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As a rule of thumb you generally do not want to set your contours to be any smaller than your cell sizes. There is no point in doing so because even if there were 3 different values across the 30m cell, it would all be averaged to the same. If you are using a 30m DEM the lowest contours you should use is 30m, as that preserves the accuracy of the data and ...


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Now, the answer from the developers of the tool, who kindly allowed me to forward the answer here. I translate and do my best to reproduce what I learnt from Dr. Conrad: The only expected input-dataset is the DEM. The tool runs an interative procedure which works with relative relief-position. The same procedure is used to calculate - the vertical distance ...


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based on your question, it seems like you want to convert raster data into vector where the raster value represent as it's attribute.. you can use raster to point or polygon tool on arcgis, the pixel value will be replace as grid code on it's attribute.. the resolution of dem will impact on distancd between point...


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You can use either polygons or points, which you choose depends on whether you need to update large areas or just individual cells. Once you've got your points/polygons created with an attribute table column with the values you want to use to replace values in the DEM with, convert the feature class to raster with the Feature to Raster tool (or the Point ...


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It sounds like you'll need to source some more data. There's no way to expand your DEM or Contours without actually finding data. I'd suggest that you look into your local, regional, or national government spatial agencies. Perhaps search for open data repositories in your area. If all else fails, there's a global elevation model at around 30 m resolution ...


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With my experiences with LiDAR pointcloud data (.las) files and LAS Tools you can set your own resolution. First you will need to filter out anything that isn't ground or water to get an accurate DEM filter. From you can use the LAS Toolset to create a LAS Dataset (.lasd) and from there you can create a DEM raster by using the LAS2DEM tool. Here is where you ...



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