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I have two raster layers that are identical in shape (they overlap exactly) and I need to perform the raster equivalent of a Spatial Join (one to many). My files need to stay in raster format otherwise I would just do everything in vector. I'm using ArcMap 10.1.

My "buffrast" raster contains the land cover value for each pixel within a circular buffer of 150m around a bunch of pointa. My "rr1" raster contains the identities for individual 150m radius circles around various points (e.g. NR0602), but has no land cover value.

I need to have a final raster whose attribute table lists the land cover value for each pixel within a given 150m radius circle. That is, I need to have the circle's identity (e.g. NR0602) listed for each pixel along with its land cover value. I've already tried raster mosaic, raster calculator (combine) but I think my syntax must be incorrect.

I am completely new to raster analysis so please be as explicit as possible in any advice you might have.

Thanks! alyssa

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marked as duplicate by whuber May 16 '13 at 22:40

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@Radar (as well as upvoters of your first comment), rasters can possess attribute tables and often do. The raster values are indexes into the table rows (tuples), which explains how they can have multiple values. Also, given that the inputs are both rasters, we should automatically favor raster-based solutions (due to the cumbersome and potentially error-prone nature of raster-to-vector conversion), so the OP should not feel obliged to explain why a vector solution is not sought. –  whuber May 15 '13 at 19:34
    
Alyssa, what software are you using? What specifically was the problem with your use of combine, which sounds like the right solution? –  whuber May 15 '13 at 19:36
    
I'm removing my original comment because it was too generalized and my terminology may be confusing. My point was, don't treat raster and vector data as the same thing - the same terminology (e.g. attribute table) may be used to describe a similar thing, but there may be nuances to that thing that make them different (e.g. indices and tuples vs. a vector attribute table). –  Nick Ochoski May 15 '13 at 19:53
    
@whuber I'm using ArcGIS 10.1. And when I do combine (which from what I understand involves simply typing in "buffrast" + "rr1" to the Raster Calculator) the resulting raster's attribute table has unique values attributed to each pixel instead of carrying over the land cover value and point value (e.g. NR0602) from each input raster. Make sense? –  Evergreen May 15 '13 at 20:08
    
That's addition, Alyssa. See the help page for Combine. –  whuber May 15 '13 at 20:10

1 Answer 1

up vote 0 down vote accepted

I figured out what I needed to do in order to display the information I wanted. I wanted to know the area of each particular land cover type within each labelled circle of 150m (basically the sum of raster cells for each land cover type)...turns out what I needed to do was use the "Tabulate Area" tool in Spatial Analyst (Zonal).

Sorry for the confusion in the way that I asked the question.

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