Can I solve system of equations in labview????

[Moony]

Hi all !!!

I would like to know, can I solve system of equations in Labview?

For example,

5a+7b=15

19a-4b=125 

(Of course, real equations have much more difficult description...)

Thanks in advance. 

[yenknip]

LabVIEW, like any other programming language won't solve simultaneous equations for you. However, if you can define the problem, you can work out a solution. Think in terms of inputs, outputs and algorithms.

If you want some help working out a maths function, we can help you out

[altenbach]

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@Moony wrote:

(Of course, real equations have much more difficult description...) 

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The linear system you showed can easily be solved by using "solve linear equations".

 

I have no idea what you mean by "real equations"?  Do you simply have more unknowns and larger matrices? If your real equations are completely different, you should probably give a more specific example.

[Moony]

Thanks for your replies!!!

Here is my equations:

9.91168E-14=F0*(exp(-Alfa* 4.455E-5)-exp(-Alfa*0.0001)/(1+0.00005*Alfa))

1.05472E-12=F0*(exp(-Alfa* 4E-5)-exp(-Alfa*0.0001)/(1+0.00005*Alfa))

I must find values of Alfa and F0.

Can you give me the way of the solution?

Thank you in advance.. 

[altenbach]

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Moony wrote:

9.91168E-14=F0*(exp(-Alfa* 4.455E-5)-exp(-Alfa*0.0001)/(1+0.00005*Alfa))

1.05472E-12=F0*(exp(-Alfa* 4E-5)-exp(-Alfa*0.0001)/(1+0.00005*Alfa))

I must find values of Alfa and F0.

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Your two formulas are the same except for a constant and could be described as y=f(x):

y(x)=F0*(exp(-Alfa* x)-exp(-Alfa*0.0001)/(1+0.00005*Alfa))

And you have two points:

1. (x=4.455E-5; y=9.91168E-14)

2. (x=4E-5; y=1.05472E-12)

You could simply use a nonlinear curve fit with the above formula model and the two data points to find F0 and alpha.

[Moony]

OK. Thank you so much.

I'll try it. 

[Moony]

Dear Altenbach, 

I tried to use nonlinear curve fit, but I have some difficulties...

Please, send me an example, if you can...

Thank you in advance. 

[RavensFan]

Fourteen minutes wasn't a long time to try.  If you are having problems, you should post what you tried so Altenbach can see where you are going wrong and suggest improvements.

[altenbach]

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Moony wrote:

I tried to use nonlinear curve fit, but I have some difficulties...

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What are the difficulties? (starting LabVIEW? writing the program? fit does not work? computer bursts into flames?)

What is your LabVIEW version?

Do you have a reasonable guess for F0 and alpha? 

[Moony]

I don't understand where I must write my formula...