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I am trying to create a TPI from a DEM tiff file in SAGA but keep getting the following result:

enter image description here

I'm just not sure what I'm doing wrong.

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    What steps are you taking to get there? – MaryBeth Apr 11 '17 at 15:05
  • I edited the picture to show my initial steps. – ATomz Apr 11 '17 at 16:10
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I think the problem may be in your value range. Try restreining it to a more reasonnable range to "see" something.Check in the description TAB to get the min/max of the pixel values and/or check the histogramm. You'll see if your problem is in the visualisation of your data or if it's elsewhere. I'll edit my answer when i have more info. You should get things like the following in the description TAB :

Value Minimum
1
Value Maximum
949
Value Range
948
No Data Value
-32767
Arithmetic Mean
456.3380409647518
Standard Deviation
181.1010906092993
  • Value Minimum -278412803253911390000000000000000000000 Value Maximum 165542745413924520000000000000000000000 Value Range 443955548667835910000000000000000000000 No Data Value -99999 Arithmetic Mean -6024139599527926900000000000000000 Standard Deviation 2680824225999367800000000000000000000 I got these unusually large values – ATomz Apr 11 '17 at 17:10
  • wow ! indeed it seems very unusual. Do you have extra info on your DEM ? – gisnside Apr 11 '17 at 17:27
  • javacoeapp.lrc.gov.on.ca/geonetwork/srv/en/main.home If you go to this site and search "Digital Elevation Model" under the "What?" search bar in the top left corner, the metadata will be there to view in the first record of the results. – ATomz Apr 11 '17 at 18:50
  • @ATomz please, provide a direct link to the resource instead of launching a treasure hunt. – mgri Apr 12 '17 at 6:46
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    Or shorter in this PDF: javacoeapp.lrc.gov.on.ca/geonetwork/srv/en/pdf?id=805 or via this permalink : javacoeapp.lrc.gov.on.ca/geonetwork/srv/en/… – gisnside Apr 12 '17 at 14:19

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