Perform Calculations on Feature Layer Data?

Discussion created by albrightjr on Jan 7, 2011
Hi All,

I am trying (unsuccessfully) to perform calculations on the attribute data of a feature layer, and then display the results as graphics. I am using the JavaScript API accessing the ESRI Sample Server 1 (9.3.1), as this is a proof of concept.

My example is using the Demographic Feature Layer: coarse counties (ID3) with the Definition Expression set to Pennsylvania and the outfield set to Population (POP2000).  Population would then be multiplied by 1,000 (eventually a user defined value) and update the class break render, so the map/counties would change based on the change (calculation) in population.

1) Is this possible?
2) Is this the right approach or would a different approach be better/work?
3) I had read a post that touched on needing ArcServer 10 to do this, is that true?

Any advice/help is greatly appreciated!