topic Problem extracting values by attributes from raster in Data Management Questions

Problem extracting values by attributes from raster

MichaelSawlan — Wed, 05 May 2010 02:08:04 GMT

I have a raster (a DEM) in GRID format, source type = continuous, pixel type = floating point, 32 Bit. The field names do not display when I attempt to use this raster in Extract by Attributes tool, nor when I select Properties > Fields of this raster. Does the Extract by Attributes tool not work with floating point data? I got this to work by using raster math INT function but this truncates decimals. Is there a simple workaround other than multiplying raster values by, say, 1000 (to keep three decimal places of value)? Thanks.

Re: Problem extracting values by attributes from raster

ChrisGraves — Fri, 27 Aug 2010 00:57:58 GMT

Hi,

Did you ever get a response on your thread?

I am experiencing the same issue even though the help documentation for extract by attributes

says it will take a floating point data-set.

Thanks,

Chris

Re: Problem extracting values by attributes from raster

DanPatterson_Retired — Fri, 27 Aug 2010 10:23:54 GMT

A DEM is probably a floating point grid, hence, there are no fields, but you can still query its "value" as in the attached examples, where a dem was queried for values > 20

Re: Problem extracting values by attributes from raster

EvanJackson — Mon, 23 Jun 2014 04:48:01 GMT

I know this post is old, but it's still relevant and good advice. Thanks.

My advice is to follow what's in the image above and keep a SPACE between the operator and numeral.

e.g. "Value" <= 0 NOT "Value" <=0.

kept on getting error messages on such a trivial issue!