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I have a floating point-valued raster which I need to convert to polygon as follows

Put the cells with VALUE < 0.5 into (a small/the smallest number of) polygons

Cells in the range [0.5, 1] into polygons

and so on..

I looked at the Raster to Polygon tool, but there is no place to specify range values. Is there a tool in ArcGIS Desktop/Toolbox for doing this?

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  • You can create your polygons from your Raster to Polygon output. Make a selection by attributes then copy the select features to a new feature class. – evv_gis Oct 21 '14 at 17:44
  • @evv_gis This is a good approach too but the raster-to-vector conversion is a much more computationally expensive operation than the selection. So if it is a massive raster with numerous complicated polygons you'll be wasting a lot of effort vectorizing them only to subsequently remove them from the vector. – WhiteboxDev Oct 21 '14 at 17:46
  • I honestly misread the post - I thought the OP said they had used the tool already. – evv_gis Oct 21 '14 at 17:47
  • @evv_gis I do that all the time too ;) – WhiteboxDev Oct 21 '14 at 17:48
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I would use either the Con or Reclassify tools to create a new raster with the value range that you are interested in and then perform the raster-to-vector conversion on this newly created raster. Two steps and you're done!

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  • This is more efficient than the evv_gis approach. Any reason not to use reclass and create a binary raster then polygonize this? – If you do not know- just GIS Oct 21 '14 at 18:06
  • @usertwoseventwothreenine In my initial comment (now deleted) I suggested using either Reclass or Con, but given it's just a Boolean raster being created, Con really will fit the bill nicely. Reclass is better suited to more complex operations in my opinion. Of course both will do though. – WhiteboxDev Oct 21 '14 at 18:19
  • Funny I think the other way. Reclass simple operationss and Con more difficult. Would be good to have a poll. I wonder which one of us in non-traditional or if it would be close to 50/50? – If you do not know- just GIS Oct 21 '14 at 18:21
  • @usertwoseventwothreenine That sounds like an interesting question to post! When to use a Conditional Evaluation tool versus a Reclassification tool? You should do it. In light of your view on things, I'll edit my answer to include Con/Reclass. – WhiteboxDev Oct 21 '14 at 18:27

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