How to find error/uncertainty value on MatLab

Hi,

Please can anyone tell me how I am able to find the error/uncertainty value on MatLab of plotted data (linear fitting model).

Many thanks

Answer 1

[Star Strider]

I am not certain what uncertainty values you want, but the File Exchange contributions polyparci (link) and polypredci (link) should provide them. They run in MATLAB and do not require any Toolboxes.

[Rik]

If you are using the polyfit function, you can get the error with this syntax: [p,S] = polyfit(x,y,n)

[Star Strider]

I never have.

What’s the error? How are you calling it to get the error?

That syntax is even quoted in the documentation for polyfit:

• [p,S] = polyfit(x,y,n) also returns a structure S that can be used as an input to polyval to obtain error estimates.