Digital Elevation Model (DEM), which could be a Digital Terrain Model (DTM) or a Digital Surface Model (DSM).

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USGS DEM Easting and Northing metric and unit

Greetings to all! First post in here. Firstly, I am a complete noob in geography. But I have to do some programming work with DEM files. I got some DEM files from ...
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How to a convert LiDAR XYZ files to DEM / DSM?

Normally consultants (LiDAR survey) provide me with data to my specifications; already in ESRI GRID or ASCII GRID format. This way LiDAR data can be easily used with ArcGIS. This time I only have xyz ...
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Code to calculate elevation profile along line from a DEM

Given a DEM (Digital Elevation Model) say in and a line (x1,y1) --> (x2,y2) (paired coordinates (x,y)), how can one calculate the elevation profile or cross-section projected on that line ? I am ...
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Where can I download 1 arc-second elevation data for Canada other than Geobase?

Can someone suggest a source for Canadian elevation data better or equivalent to 1 arc-second? I have a good data source for Ontario but for other provinces folks often recommend Geobase which claims ...
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Problems merging DEMs or other raster datasets? Clipping Raster dataset to vector line?

I have two DEMs that I am going create a hillshade from, and ultimately want one hillshade clipped to a county boundary. I am running into a couple problems, though. When I try to merge the two ...
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How can I convert a DEM into areas of “flatness”, with an arbitrary fill/cut to area ratio?

I want to find areas of relative "flatness" in a DEM. How can I find flat areas? I want to find a neighbourhood of contiguous cells that have an elevation variance that is within a certain ...
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Are there any open source tools to detect and fill sinks on a DEM?

Are there any open source or inexpensive tools to detect and fill sinks on a DEM? ESRI Spatial Analyst is just out of my price range.