solving N equations N unknowns

[Milade8080]

hi
I want to design a form in Microsoft Access below one can help me, Tank you

Form 1
Enter the number of unknowns (or equations)


then in Form 2
Enter the unknown coefficients

 

[pr2-eugin]

Hello Milade8080, what is your question again? Give some examples. Your description makes no sense TBH !

 

[Mihail]

Do you know how to do this manually ?
Can you post the algorithm ?

 

[Mihail]

Do you know how to do this manually ?
Can you post the algorithm ?

What you know about Access ?
Are you aware that under each form is a table or a query ?

Do you know at least how to test if a system of equations has solution or not ?
Are you able, by using your math to solve this:
x+y=0
3x+2y=0
????????

 

[jdraw]

Form 1
Enter the number of unknowns (or equations)

then in Form 2
Enter the unknown coefficients

And then what? You click a button and.........

 

[gemma-the-husky]

isn't there a solution for simultaneous equations using matrix mathematics?

I vaguely remember being shown this in school

that's the way to do it, I think?

 

[Mihail]

isn't there a solution for simultaneous equations using matrix mathematics?

I vaguely remember being shown this in school

that's the way to do it, I think?

Yes, it is. But is not very easy to program the algorithm.
Even if it is possible to use Xk = DXk/Dx (k=2,3 ... n) the algorithm to calculate D (sorry, I don't know the English word) is not a breeze.
And this approach is far away from the best one.

 

[gemma-the-husky]

well there must be some formula for solving a set of simultaneous equations

note that if you have more variables than equations, you will have a Diophantine equation.

 

[AOB]

Mihail, I believe the method you are referring to is Gaussian Elimination

Rows representing each linear equation, columns representing the variable coefficients. You then use row and column operations to reduce the problem down to one coefficient (i.e. a matrix of zeroes apart from one row) Then use substitution back to determine the remaining coefficients.

As Dave mentioned, this requires at least one independent equation for each coefficient. In other words, no two equations can be derived from each other (e.g. x+y=1, 2x+2y=2 - these are basically the same equation, just one multiplied by the other). So the initial matrix should be square (i.e. same number of equations as coefficients)

I'm sure it's possible to automate somehow as the process is fairly logical. But would have thought Excel would be a better place to do this rather than Access?

 

[Mihail]

Mihail, I believe the method you are referring to is Gaussian Elimination

Rows representing each linear equation, columns representing the variable coefficients. You then use row and column operations to reduce the problem down to one coefficient (i.e. a matrix of zeroes apart from one row) Then use substitution back to determine the remaining coefficients.

As Dave mentioned, this requires at least one independent equation for each coefficient. In other words, no two equations can be derived from each other (e.g. x+y=1, 2x+2y=2 - these are basically the same equation, just one multiplied by the other). So the initial matrix should be square (i.e. same number of equations as coefficients)

I'm sure it's possible to automate somehow as the process is fairly logical. But would have thought Excel would be a better place to do this rather than Access?

A bit of Google and a lot of solutions:
https://www.google.ro/search?q=linear+equations+systems+algorithm&btnG=Căutaţi&hl=ro&biw=&bih=&gbv=1
What I said is that is not an easy task to code this algorithms.
It is not impossible while I do this years ago on a Spectrum "computer" (48 Kb memory and Beta-BASIC as programming language - what times...).

Rows representing each linear equation, columns representing the variable coefficients. You then use row and column operations to reduce the problem down to one coefficient (i.e. a matrix of zeroes apart from one row) Then use substitution back to determine the remaining coefficients.

Indeed that was my approach. I remember that I used the back-tracking method here, with a procedure that have had calls to itself. But there are more than 30 years from this.

 

[AOB]

Nice link Mihail! Think you can do it iteratively as well with confidence intervals?

I used to do something similar on a BBC Micro Model B (32kB )

Also BASIC

Good times. Sigh.

 

[Milade8080]

I'm sorry but a lot Eminem: BULLSHIT this site because you have 10 posts to get put off limits, these limits led to the precise details of my goal I can not
I'm really sorry that I was a member of this site

 

[Milade8080]

I have not seen any site that may be so restrictive

 

[Milade8080]

I am an Iranian and an Iranian, I am proud of all the websites that have no restrictions, but the users of this site such as Mihail and gemma-the-husky .... and I thank that followed.

 

[Milade8080]

Aob and Mihail tank you

Aob and Mihail از شما تشکر میکنم

 

[Milade8080]

Eliminate restrictions - post 6

 

[Milade8080]

Eliminate restrictions - post 7

 

[Milade8080]

Eliminate restrictions - post 8

 

[Milade8080]

Eliminate restrictions - post 9

 

[Milade8080]

hi
I want to design a form in Microsoft Access below one can help me, Tank you

form 1:

next form :

Works done by Visual Basic:
http://www.codeproject.com/Articles/...mial-Equations