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I am currently working on a research project in a lab, and I am fairly familiar with ArcGIS (I'm only in high school and have done some previous work using ArcGIS). I was asked to add 3 columns onto a data set (a csv file with XY coordinates). These three columns are supposed to come from rasters, and so far I have had no luck. So far I attempted to:

  1. Extract data by points from the rasters
  2. Join the files
  3. Convert the csv file to a shape file and then attempted to join the three rasters (before I projected the rasters and after)
  4. Adding XY coordinates to the shape file and then joining
  5. Projecting the rasters and then join based on the FID/Object ID

I feel like this is impossible.

closed as unclear what you're asking by PolyGeo, Brad Nesom, Jason Scheirer, Paul, BradHards Jul 12 '14 at 23:50

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.

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    There have been two different interpretations of your question made by its answerers. Would you be able to edit your question to state clearly what data type these new columns will have e.g. float, integer, raster, text, etc? Also, can you make it clear whether you have tried and succeeded in creating point features from your CSV file which will I think be the first step either way. – PolyGeo Jul 11 '14 at 23:22
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I suppose that you need the value of the raster in your column at the location of your points.

first, convert your csv to a shapefile (make XY event layer). You should check that your coordinate systems are correctly set (at least, the points must fall on top of the raster). Try to avoid projecting your raster, because resampling often modifies the raster.

second, use extract multivalue to point. The three raster must be in the same projection.

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The shapefile format does not support raster columns.

There is a help page entitled Adding raster datasets as attributes in a feature class that says this explicitly and offers a workaround:

A shapefile cannot contain an attribute field to hold raster datasets. In this case, it would be advantageous to use a hyperlink.

If using a shapefile is a mandatory requirement then the above workaround should be used.

However, if you have flexibility to use a file geodatabase feature class instead of a shapefile then that would enable you to store raster columns.

  • I believe your lead sentence may be based on a misinterpretation of the question: it is not asking about shapefile structure but only about how to extract raster information and copy it over into shapefile attributes. The basis for my interpretation is the workflow presented in the question: see step 1. – whuber Jul 11 '14 at 13:12
  • @whuber I think you may well be right but the "steps" seem to be what has been tried rather than a workflow. I'm going to vote to close as unclear to try and get more information from the asker. – PolyGeo Jul 11 '14 at 23:18

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