markandersen

Finding sum of values in floating point raster

Discussion created by markandersen on May 10, 2010
Latest reply on May 11, 2010 by markandersen
I am trying to find the quickest way (in terms of processing speed) to find the total (sum) of all values in a raster.  In other words, I am looking for a tool that will add the value for all cells within a particular raster, and just give me that value as a number.  Ideally, this would spit out a table with just one row, as the "Get Raster Properties" tool does.  The "Get Raster Properties" tool in the "Raster Properties" toolbox in ArcToolbox looks like it is very close, in that it provides summary statistics for a raster, but there are two problems: 1) there is not an option for "sum"; and 2) it appears to round-off the answer to 6 decimal places, and I need much greater precision than that.

The only way I've found to do this is to use the "Zonal Statistics As Table" tool and set a dummy "zone" raster that has a single value ("1") for all pixels covering my study area, so that it is finding the statistics (including sum) for all cells in the raster.  However, this is pretty slow--mostly because I think it's comparing each pixel to see which zone it's in. 

It seems that there should be a built-in way to get a sum of all cell values in a raster.  Help!

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