No, it's basically 'six-of-one, halfdozen of the other', just that NX supports both approaches.
OK for a fully standalone part containing all of the spreadsheet logic, if you have an existing spreadsheet with a full set of formulas which resolve to the values that you would now like to drive your NX model, what you need to do is first create your model with all the varibles (expressions) needed to drive the parameters of your Sketch or modeling features as desired. Now go to...
Tools -> Spreadsheet...
...and when the Excel window opens, go to the 'Office Button' and Open your existing spreadsheet. Now select either the whole page or just the cells that you wish to reuse and hit 'Copy'. Now close YOUR spreadsheet and Paste the contents of your Copy into the Spreadsheet which was opened by NX. Now you have your data in the NX part file, however you still need to hook it up to your model. So select some random cell near where your formulas/data is located and select the 'Add-Ins' tab at the top of the Excel window, and from the list of function on that tab, select the one titled 'Extract Expr' and all of your expressions from your model will be inserting into the spreadsheet. If there any expressions which there is no need to create links to, you can simply delete them. Of the expressions that you do wish to link to, simply edit the 'value' cells so that they are set equal to the appropriate cells of your original spreadsheet data.
Now to force the NX model to update using the new data go back to the 'Add-Ins' tab and select the item titled 'Update NX Part'. Once that the update has finished you can simply exit/close the Excel window, but when you do you will be asked if you wish to save your spreadsheet data or not. You will want to select OK so that it's saved INSIDE the NX Part file. Remember, you must always perform the 'Update NX Part' operation from within the spreadsheet for the NX model to update. If you do not, when you leave the spreadsheet and return to the Part file nothing will have changed.
Now when you wish to make future changes using your spreadsheet data, simply go back to...
Tools -> Spreadsheet...
...and you will find all of your data is still there in the Excel window. Simply make your changes, select the 'Update NX Part' option once more and then return to the NX session by exiting/closing the Excel window (always remembering to select OK when you exit so that the spreadsheet changes are saved).
Anyway, I hope this helps you accomplish what you looking to do.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
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