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I have about 500 elevation rasters, and I would like to use modelbuilder with an iterator to reclassify each raster into distinct elevation ranges (0-1m, 1-2m, 2-3m, 3-4m, 4-5m). I believe my problem is that each raster has a different range of elevation, is there a work around this? I tried mosaic-ing all the rasters together but reclassify tool does not work on this mosaic.

  • Are you using a continuous DEM in floating point format? – Aaron Jun 26 '14 at 14:18
  • yes it is a floating point – tugboat789 Jun 26 '14 at 14:25
  • What happens when the reclass fails? Have statistics been calculated on the DEMs? – Aaron Jun 26 '14 at 14:35
  • Yes I calculated all statistics. I use Iterate rasters and the Reclassify tool and I get the error message "The Input maximum (6.784375) is out of range.." – tugboat789 Jun 26 '14 at 15:11
  • Why not create another class >5m? – Aaron Jun 26 '14 at 15:12
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Create a CSV file:

Low,High,Val
0,1,1
1,2,2
2,3,3
3,4,4
4,5,5

It is best to import it to a dbf, INFO or GDB table after entering the text values.

Then use Reclassify by Table, it doesn't care what the ranges of individual rasters are. According to the documentation, build the statistics first then run this tool (iteratively if you like). From_value_field is Low, To_value_field is High and Output_value_field is Val. Change the numbers in the Val column to suit your expected outputs, the values I have shown here are illustrative only.

Depending on what you want in your output you can specify Missing Values: DATA which will copy all values not listed in the table as they are or Missing Values: NODATA which will set all values not in the table to NODATA.

  • Hi, I am creating a csv file with exactly what you wrote (3 columns with my own "val" column) and using Reclass by Table and selecting missing values as no data. I am getting ERROR 010328 and ERROR 010267. Both syntax errors. Any idea what I could be doing incorrectly? – tugboat789 Jul 1 '14 at 14:24
  • Is there anything with the errors. Could you get a screen grab and post it with the question. Did you try to use the CSV directly or did you import it to another table format as suggested? If you converted it does the table look correct? – Michael Stimson Jul 1 '14 at 21:43
  • I see that I made the mistake of not importing the .csv file into a gdb first. I began the reclass by table tool again and got no error message. Unfortunately it has been running for 6 hours for one raster so am not sure this will actually work. It could be that I am working with LIDAR data which is much more intense and does take a long time to process. – tugboat789 Jul 2 '14 at 20:15
  • Been down that road before, CSV isn't the best format. How big is your LiDAR dataset? Perhaps clip a small bit out to prove it's working before running it on a large dataset. Also look at your TEMP and TMP environment variables, most Esri raster functions copy the raster to the temp/tmp directory and process it there; you may be having quota/disc problems in your temp directories. – Michael Stimson Jul 2 '14 at 21:48
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    @Zery, numbers are just numbers. Percents range from 0 to 100, however in the case of slope in rare instances values can be greater than 100 i.e. more than 100% vertical increment for the horizontal displacement. If you need to get min & max you can get that from a arcpy.Raster object and write the table on the fly using python file I/O; I think in this case if you made the last band 100.0 to 1000000.0 that should be a general catch-all. – Michael Stimson Oct 29 '14 at 21:35
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I ended up having to use Feature Analyst (extension from Overwatch) and used "Image Fusion" tool and clicked "custom", clicked band 1 and input a script assigning values to elevation classes. Then I used batch processing in Lidar Analyst extension to batch process all of the rasters this way. I think regular GIS tools sometimes have trouble handling a lot of LIDAR data

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