Extract by mask ... No Attribute Table!!!

Question

Hello,

How can I extract/clip a shape from a raster WITH the attribute table?  In Arc 9.3 I would simply extract by mask and the output would automatically have the assoicated attributes... using the same raster and feature in Arc 10 I get a blank output with no attributes... What am I missing?   I need the attribute table in order to run stats... I've tried building an attribute table, which fails... Any help would be super!!

Thanks.

curtvprice · Answer

I have clipped the raster to a specific shape and just need to retrieve the statistics so that I can determine the average pixel value in the shape.
Any ideas on getting the statistics/attribute table for a float raster?

Float rasters cannot have attribute tables.

As for getting the statistics, if that's all you want, you could have used Zonal Statistics As Table to get the value.

If you need the raster too, you can access statistics by viewing the raster properties, (see Raster data statistics) or if you need to get at the number inside a model or script, try the Get Raster Properties tool.

AlexandraBarker · Answer

Hi, thanks for the response!

I tried to build the attribute talbe but this doesn't work as the raster is in float format. 
I have clipped the raster to a specific shape and just need to retrieve the statistics so that I can determine the average pixel value in the shape.
Any ideas on getting the statistics/attribute table for a float raster?

Thanks,

Ally

curtvprice · Answer

Ally,

Integer rasters [post=297376]don't always have the attribute table built[/post] depending on the range and number of values. This was true in 9.3 and it is still true.

You may need to run the Build Raster Attribute Table tool to get one. (If there is one there already, no harm done.)