ExcelBanter

ExcelBanter (https://www.excelbanter.com/)
-   Excel Discussion (Misc queries) (https://www.excelbanter.com/excel-discussion-misc-queries/)
-   -   Question about the Solver Addin (https://www.excelbanter.com/excel-discussion-misc-queries/98880-question-about-solver-addin.html)

Mark

Question about the Solver Addin
 
How can I make the solver produce the same solution (i.e., "By Changing
Cells") run after run assuming no change to the underlying data?

Maybe by solver's nature this is impossible.

The model is fairly simple. At one point I thought if the initial values in
the "By Changing Cells" remained the same, the final solution (i.e., in "By
Changing Cells) would be unchanged assuming no changes to the underlying
data. This however does not seem to be true.

Thanks for your comments.

Mark

Franz Verga

Question about the Solver Addin
 
Mark wrote:
How can I make the solver produce the same solution (i.e., "By
Changing Cells") run after run assuming no change to the underlying
data?

Maybe by solver's nature this is impossible.

The model is fairly simple. At one point I thought if the initial
values in the "By Changing Cells" remained the same, the final
solution (i.e., in "By Changing Cells) would be unchanged assuming no
changes to the underlying data. This however does not seem to be true.

Thanks for your comments.

Mark



Hi Mark,

Are you sure that nothing change in your model?

Maybe you have a cell that use the NOW() function: try to replace it with
TODAY().

Maybe you have some cells with RAND() function: replace the function with
values (copy & past special, values).

Or maybe your problem has more than one solution...


--
Hope I helped you.

Thanks in advance for your feedback.

Ciao

Franz Verga from Italy



Mark

Question about the Solver Addin
 
Franz -

First of all - congrats on Italy winning the World Cup.

The model doesn't have anything changing from run to run.

I'm sure the model has multiple solutions. But given the multiple solution
model, is there a way to make Solver produce the same solution run after run,
assuming no changes to input?

I thought using the same inital values (run after run) in the "By Changing
Cells" would do the trick. On the tests that I have run since I wrote this
question, keeping the same initial values, has done the trick. So maybe this
is the answer.

It would be nice to get confirmation.

Thanks,
Mark





"Franz Verga" wrote:

Mark wrote:
How can I make the solver produce the same solution (i.e., "By
Changing Cells") run after run assuming no change to the underlying
data?

Maybe by solver's nature this is impossible.

The model is fairly simple. At one point I thought if the initial
values in the "By Changing Cells" remained the same, the final
solution (i.e., in "By Changing Cells) would be unchanged assuming no
changes to the underlying data. This however does not seem to be true.

Thanks for your comments.

Mark



Hi Mark,

Are you sure that nothing change in your model?

Maybe you have a cell that use the NOW() function: try to replace it with
TODAY().

Maybe you have some cells with RAND() function: replace the function with
values (copy & past special, values).

Or maybe your problem has more than one solution...


--
Hope I helped you.

Thanks in advance for your feedback.

Ciao

Franz Verga from Italy




Franz Verga

Question about the Solver Addin
 
Mark wrote:
Franz -

First of all - congrats on Italy winning the World Cup.


It was hard, but we did... :-)

The model doesn't have anything changing from run to run.

I'm sure the model has multiple solutions. But given the multiple
solution model, is there a way to make Solver produce the same
solution run after run, assuming no changes to input?

I thought using the same inital values (run after run) in the "By
Changing Cells" would do the trick. On the tests that I have run
since I wrote this question, keeping the same initial values, has
done the trick. So maybe this is the answer.

It would be nice to get confirmation.



Yes, if the model has multiple solutions, to have always the same result you
have to use the same initial values.


--
Hope I helped you.

Thanks in advance for your feedback.

Ciao

Franz Verga from Italy




All times are GMT +1. The time now is 07:13 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
ExcelBanter.com