Using Macros to Calculate Matrix Algebra in Excel..... I'm STUMPED

[Still Learning]

Hello!
Here is a link to a file with my situation:

http://www.savefile.com/files/8301241

I need to find a way to set up a spreadsheet where I can input the variables
G, H, W, J, Q, S and have excel calculate the possible answers that satisfy
all of the equations in column D.

I know to do this on paper you use matrix algebra but I have no clue how to
do this in excel.

Column B is the results I should be getting for each variable in column A
(with the input values in column F) but I can't get it to work in excel.
Column C is a quick attempt I made to use iterate and circular references but
to no avail. If anyone can point me in the right direction I would REALLY
appreciate it. Oh and column A is a list of all variables used in the
equations in column D.

Is it even possible to input values for the variables in column E and have
excel use those to find answers that satisfy all of the equations in column
D??

[Tristan]

Hi there,

This shouldn't be too hard to execute.

When you work out your F variable you could rewrite the formula as:

F=A*((G*0.1)+(H*0.2)+(W*0.65)+(J*0.05))

You can get separate cells to perform each part of the calculation i.e. One cell, say A1, peforms the "G*0.1", another, A2, "H*0.2" etc and when you write the formulas into the cell you can reference back to the cells where you're inputting your variables (in your file (G*0.1) would be "=F2*0.1".

You know what F is because it equals T and that's derived from values which you know or are inputing.

So all you need to do is switch the formula round so that:

A= F / ((G*0.1)+(H*0.2)+(W*0.65)+(J*0.05))

The formula you write into the cell will be something like:

= A5 / (sum(A1:A4))
The rest of the formulas write themselves.

Anyway, I've put this all onto sheet2 of your file and hopefully I can attach it to this post. It might make a bit more sense on there.

Hope this helps

Tris

[Still Learning]

Thanks for the help Tristan! For some reason the link didn't work, would it
be possible for you to e-mail it to me at [email protected]?

"Tristan" wrote:

>
> Hi there,
>
> This shouldn't be too hard to execute.
>
> When you work out your F variable you could rewrite the formula as:
>
> F=A*((G*0.1)+(H*0.2)+(W*0.65)+(J*0.05))
>
> You can get separate cells to perform each part of the calculation i.e.
> One cell, say A1, peforms the "G*0.1", another, A2, "H*0.2" etc and when
> you write the formulas into the cell you can reference back to the cells
> where you're inputting your variables (in your file (G*0.1) would be
> "=F2*0.1".
>
> You know what F is because it equals T and that's derived from values
> which you know or are inputing.
>
> So all you need to do is switch the formula round so that:
>
> A= F / ((G*0.1)+(H*0.2)+(W*0.65)+(J*0.05))
>
> The formula you write into the cell will be something like:
>
> = A5 / (sum(A1:A4))
> The rest of the formulas write themselves.
>
> Anyway, I've put this all onto sheet2 of your file and hopefully I can
> attach it to this post. It might make a bit more sense on there.
>
> Hope this helps
>
> Tris
>
>
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