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I'm working on a tool for classifying bridges with GRASS. I have been using examples online but I've come to a standstill as how to actually make this tool in GRASS. I have my raster of my area and tagged bridged areas with a shapefile but I'm not sure what else I need to do. I've been told to use the R statistical package so if any one has any knowledge with that then I would greatly appreciate it. Thank you!

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On what basis are bridges "classified"? Could you perhaps provide links to the online examples you mention? – whuber Mar 27 '12 at 19:29
I'm hand tagging bridges based on known locations, but the tool is suppose to get statistical data from these areas and be able to classify bridges on a larger raster map. I'm just not sure how to utilize GRASS to make this a reality. This is the study that my project is derived from [link] – BurmesePython Mar 27 '12 at 20:12
So is your problem to be able to identify bridge and bridge-like structures from high-resolution DEMs?--that's the thrust of the paper you reference. If you have already identified them, then there doesn't appear to be anything left to do. Perhaps it comes down to the "statistical data": what does that mean? (The phrase is so vague it could be anything, but it sounds like you have something specific in mind, such as height over water, length of span, type of construction, or something like that.) – whuber Mar 27 '12 at 21:02

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