fzero - zero finder numerically in LabVIEW - NOT based on formula

[pawel]

Hello All.

Does anybody have a simmilar function to Matlab "fzero" in LabVIEW?

I do not need anything less advanced?

thanks in advance
Pawel

[mohadjer]

Hello Pawel

Have you checked out the functions in the palette "All Functions < Analyze < Mathematics < Zeros... They might be what you are looking for.

Mohadjer

[Steve8.5]

I want to use fzero to minimise a function of many variables, but with only one variable to be minimised. The other are just constants. In MATLAB I would do this by using something like :

x=fzero(@(x) myfun(x,a,b,c),x0)

where x is the variable to be minimised.

Unfortunately MathScript doesn't seem to accept the handle @, which leaves me stuck. Any ideas how to get round this problem?

Many thanks,
Steve.

[Steve8.5]

Sorry I did actually mean find the zero of the function, not minimise it.

[Karunya_R]

Hi Steve8.5,

Mathscript does accept the fzero function. Here is a link for the syntax.

I hope this helps!

[Steve8.5]

I know that fzero can be used, and works fine with one variable. My question was regarding finding the zero for a function of more than one variable, but with only one to be changed i.e. not a system of equations.

[Karunya_R]

Hi Steve8.5,

Have you tried using fsolve? Here is a link to explain the difference between fzero and fsolve.

[Steve8.5]

Yes, and that has exactly the same problem, as the problem is with the use of @ rather than with fzero itself. However, I have worked out a solution using global variables instead, so that my function can be of just one variable with the other variables passed to it by making them global.

[GrantM]

Hello Steve,

MathScript does not support the @ syntax, as you note.  A workaround is to simply type the name of the function you wish to call.  For example,
x=fzero('myfun', x0);

Also, the function parameters currently only accept one argument.  This is a limitation we are aware of.  The global variable route is the workaround we recommend.

Grant M.
Staff Software Engineer | LabVIEW Math & Signal Processing | National Instruments