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SRTM Slope Calculation

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#1
zare

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Hi,
I'm wondering if you can help me out at all. I'm working on calculating the slope by degree for an SRTM file.
I downloaded it from here http://ifile.it/0kbe....blogfa.com.zip
However I cannot manage to calculate the slope from it using the spatial analyst tools. If I select the output to be in degrees I get 2 attributes. And if I select the output to be in per cent I get numerous attributes for each but these figures are in the millions so obviously are not percentages.

I'd really appreciate a swift response as I'm in a massive rush, i upload picture
thanks,
zare

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#2
Crischan

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Downloaded SRTM tiles are in degrees (horizontal units) versus meters (vertical units). Have you transformed the data to a projected CRS with horizontal units as meters such as UTM?
Crischan Wygoda
http://wygoda.net

#3
zare

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Downloaded SRTM tiles are in degrees (horizontal units) versus meters (vertical units). Have you transformed the data to a projected CRS with horizontal units as meters such as UTM?

i transformed the data to utm project with globalmapper v.12
but still But even when I'm working on calculating the slope, i cant manage to calculated the slop
please in software arcgis 9.3 completely ant step to step explain
thank you very much

#4
jrat

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the percentages are correct. If you think bout it 45 degrees is a 1:1 slope which is 100%. Try checking the symbology of the degree slope. The information might be in the raster just not symbolized.




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