Find zeros of numeric function

Hi all,

I have a numeric function which for the sake of simplicity resembles the following:

x = linspace(1:100) ; 
y = sin(x) ; 

I would like to know if there is a function in matlab where it returns the zeros of the above (presumably based on the sign change of adjacent elements).

KR,

KMT.

EDIT: The function as I say above is numeric, hence cannot be analitically expressed (i.e. sin cosing or whatever) as it is shown in my example. I used the above example just to create to numeric vectors.

Answer 1

[ME]

You could use fzero for this. Only issue is that it returns the zero closest to a chosen start point, therefore I've put a loop in to find multiple zeros. Maybe somebody could show a more elegant way?

fun = @sin;
x=linspace(1,100);
for i=1:numel(x)
    x0(i)=fzero(fun,x(i));
end
x0=unique(x0)

[KostasK]

Yes, this could be one way that it can be done. However in this case i have a numeric function not an analytic one. So I only have two vectors of numbers essentially. I will edit my question to clarify this better.

[ME]

Well then you could look at the below if you essentially just want to find the sign changes

https://uk.mathworks.com/matlabcentral/answers/32590-find-for-sign-changes