Hi Jim,

Best practice: All input to your UDF should be included in the argument list
(of the function call and of course the function definition).
There are hardly any or even no cases where you need Application.Volatile if
you follow this practice.
Doing it this way cells with UDF calls will not be recalculated
unnecessarily.
Post again in this thread if you still have questions or doubts. Do include
your code and the formulas and values with which they are called.

--
Kind regards,

Niek Otten

"Jim Hagan" wrote in message
...
Here's the scenario ....

I have a worksheet cell that calls a user-defined function. The
user-defined function, in turn, relies on inputs from other spreadsheet
cells
that are part of an iterative calculation procedure. Since the
user-defined
function is not really needed for every iteration step (ie. doesn't change
that much), and since it's fairly computational intensive, I'd like to
have
the ability to turn off manual calculation only for that particular cell
which calls the function. After my iterative calculation procedure has
converged, I would then like to update the function value, and re-run the
iterative procedure.

Jim

"Niek Otten" wrote:

Hi Jim,

Not exactly.
But do visit:

http://www.decisionmodels.com/calcsecretsg.htm

Or, tell us what you're trying to achieve

--
Kind regards,

Niek Otten

"Jim Hagan" wrote in message
...
Hi all,

Is there a way within Excel to set the calculation mode for a single
cell
to
manual, while keeping the rest of the workbook on Automatic calculation
mode.

Thanks for any help provided,

Jim