Yes, that's not a problem.
Now there are two different approaches, in one case the 'spreadsheet' data can be embedded inside the NX part file itself, but then you can only access this data from inside of that particular NX part file. The second approach is to link the expressions to the cells in an external Spreadsheet. Based on how you put your question, I'm assuming that you're talking about using an 'external' spreadsheet and so my example will be based on that assumption.
OK, attached is an NX 7.5 part file and an Excel spreadsheet. Place the part file wherever you wish, but for now at least, place the spreadsheet file in the...
C:\Windows\Temp
...folder.
When you open the Spreadsheet you will find two values, a 'Diameter' and a 'Height' (note that the cells with names are superfluous as it's only the cells with numerical values that are of any use for this simple example). Now open the NX part file and note that there is a cylinder and that I've linked the values of the expressions for Diameter (p0) and Height (p1) to the appropriate cells in the Spreadsheet. Also note their current values.
Nw go to the spreadsheet and edit one or both of the numerical values and save the Spreadsheet. Now in NX, go to...
Tools -> Update -> Update for External Change
...and you will note that the model updated and if you look at the Expressions you will see that they are now reporting the same value(s) that you just entered in the Spreadsheet.
Anyway, that should get you started and pointed in the right direction. If you have any questions, feel free...
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
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