MATLAB: How to set a function for error propagation

Question

Hey, this is kinda my first try with

function

My aim is to code an automatic sequence for error propagation. E.g.

function [DeltaY] = equation(x)

With DeltaY being the solution and x an equation like x = a*b

As I said I have very little experience with functions, hence:

function [DeltaY] = equation(x)
DeltaY = sqrt((diff x,a)^2 * da^2 + (diff x,b)^2 * db^2)
end

does not work if I typ

equation(x)

Strikes me as I need to define a b da db seperately like

syms a b da db
x = a*b

But where to put it?

Answer 1

Yes you need to deinfe a b da and db either in the function or in your script before you call the function and also let them be inputs to your function

like this:

function [DeltaY] = equation(x,a,b,da,db)
DeltaY = sqrt((diff x,a)^2 * da^2 + (diff x,b)^2 * db^2)
end