how to develop a formula where assumed value in a cell is used to

[Guest]

i want to develop a formula where a cell value is first assumed to calculate
parameters of a machine.the parameter assumed is also obtained by calculation
.. how to ensure that assumed value is replced with calculated value and all
calculations are repeted till difference between assumed and calculated value
is less than 0.1

 

[Guest]

Hi,

The following is extracted from xl2007 help. I think it answers your first
question. (Not the answer you would like but that's life.)

Excel cannot automatically calculate a formula that refers to the cell —
either directly or indirectly — that contains the formula.

'Iteration' is the word to look up for repeated calculation. You might find
something helpful between there and the Add-in Solver but you will probably
need to place your assumed value in another cell.

Regards,

OssieMac

 

[Fred Smith]

Take a look at Tools>Goal Seek... It may do what you want.

 

[ilia]

Go to program options and find Calculations (or Formulas in XL 2007).
Turn on iterative calculations, and set the "maximum change" value to
0.1, and a desired "maximum iterations" value.

From there, since you didn't specify the formulae you're using, the

general technique I use involves this:

(1). A cell which determines whether to make the formula loop circular
(TRUE/FALSE or 1/0 value)
(2). A cell that contains the initial "guess" value
(3). A reference cell that is reused in calculation
(4). A cell that conditionally refers to the (2) when (1) is FALSE,
and to (3) when (1) is TRUE

Then, you enter your parameters, set (1) to true, and watch it go.

Hope that's helpful to your situation.