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

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??

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

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 whe
you write the formulas into the cell you can reference back to the cell
where you're inputting your variables (in your file (G*0.1) would b
"=F2*0.1".

You know what F is because it equals T and that's derived from value
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 ca
attach it to this post. It might make a bit more sense on there.

Hope this helps

Tri

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

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 ?

"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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