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I'm rather new to using ArcMap.

For my research project, I have a layer of point data. I have been downloading datasets and layers of aggregated annual precipitation across the United States.

All I need to accomplish is to simply get a spreadsheet file (.xls, .csv, or similar formats) that simply contains the rainfall (or the range of rainfall) that point falls into on the map.

condensed visual to give you an idea http://i66.tinypic.com/zkswfk.jpg

So, in the end, all I would need is a spreadsheet that has data that looks like this: point0 | 0-100 point1 | 251-500 point2 | 1,501-2,000 point3 | 0-100 ...

Can anyone help me with this?

The precipitation layer in the image above is a .PNG file.

  • When you click on raster using i does it give you expected value of precipitation, or 3 integers like 225,37, 128. If yes to 2nd, it is useless picture, some efforts needed to convert it to single band raster – FelixIP Feb 3 '17 at 9:19
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I do not have the Spatial Analyst license necessary to test this, but it looks like the two main tools in the process are:

  1. Extract Values to Points (needs Spatial Analyst license):

Extracts the cell values of a raster based on a set of point features and records the values in the attribute table of an output feature class.

  1. Table To Excel:

Converts a table to a Microsoft Excel file.

If you need to pre-process your image before it can be used by Extract Values to Points then look at Copy Raster (to change formats) and Make Raster Layer (to create the raster layer that it looks like is needed).

  • I've tried that, ArcMap will not let me use the .PNG layer as raster input data. – Bloo Feb 3 '17 at 5:24
  • @Bloo Please always tell us what you have tried when you ask your questions. – PolyGeo Feb 3 '17 at 5:34
  • Alright, will try to do that from now on. But, do you have any suggestions on how to make a .PNG file accessible to that function? – Bloo Feb 3 '17 at 6:01
  • @Bloo I had edited that into the answer: "If you need to pre-process your image before it can be used by Extract Values to Points then look at Copy Raster (to change formats) and Make Raster Layer (to create the raster layer that it looks like is needed)." – PolyGeo Feb 3 '17 at 6:04
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  1. Raster to Polygon to convert the raster to polygons
  2. Spatial Join the polygon to the Points
  3. Export table with Table To Excel
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I know this can be done in QGIS if you are familiar with the program.

If you load both the png and the sample points into QGIS and select the point sampling tool by going to the plugins tool. Once you open it, the program will ask you to select the attributes of each layer, and which is the sampling layer (yours would be the locations)

This will give you a ShapeFile that you can quickly change to CSV and bring into another program.

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