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Does anyone know how to convert continuous data (in this example a raster file) into discrete data in ArcGIS Desktop?

I need to get the values from each pixel (emissivity from satellite image) into a table, so I can join them with another layer.

closed as unclear what you're asking by ahmadhanb, Vince, whyzar, csk, nmtoken Nov 17 '18 at 10:25

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Welcome to GIS SE. Thank you for taking the Tour. There are many ways to convert raster to vector in ArcGIS. Unfortunately, your question is rather vague on what you are trying to accomplish, and doesn't give any indication of what you have tried or what error you have encountered. – Vince Nov 16 '18 at 12:16
  • Hi:) I have a raster which i calculated via raster calculator to get a general emissivity (for NDVI greater than 0,2 and smaller than 0,4). But i also have fixed values for water (negative NDVI), vegetation (greater than 0,4) and soil (0-0,2). Its only the middle part, which i had to calculate, because there is no fixed value. Now i have extracted the different "portions" of NDVI, and each part has its emissivity value in the attribute table. Unfortunately i don´t know how to join them together, because – L.R. Nov 16 '18 at 13:47
  • the spatial join, merge, join tables etc. they don´t work. I extracted the different parts by Extract by Attribute.. – L.R. Nov 16 '18 at 13:49
  • Are you wanting to end up with a single raster that combines your 'portions'? – MappaGnosis Nov 16 '18 at 13:58
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    Please Edit the question in response to requests for clarification. It's not fair to those who would answer to need to mine the comments for critical information. – Vince Nov 16 '18 at 14:44
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If I have understood you, you have an NDVI and you want to create a new, derived raster. Instead of converting to multiple vector data layers, use the Raster Calculator with a nested conditional statement on the original data (scroll down to see the complex expressions):

outRast = con(ndvi <0, 1, ((ndvi <= 0.2) & (ndvi => 0), 2, ((ndvi > 0.2) & (ndvi < 0.4), 3, 4)))

This basically says:

  1. if ndvi is less than 0 then outrast value is 1
  2. if ndvi is between 0 and 0.2 then outrast value is 2
  3. if ndvi is greater than 0.2 and less than 0.4 then outrast value is 3 (your middle portion)
  4. if ndvi is greater than 0.4 then outrast value is 4

So you get your combined final raster in one step in stead of several. You will need to edit the raster algebra above to suit your exact needs but I hope you get the idea - just be careful of all those brackets!

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