How can i find with a simpe and easy code the zero crossing of a function?

Let's say that I have a sinus wave and i want to find and plot the zero crossing for that function.How can i do that, with a simple code?

[John D'Errico]

Why not read the help for fzero? You might even find an example in there, rather than asking someone to re-write the documentation for fzero.

doc fzero

Answer 1

[KSSV]

t = linspace(0,2*pi,5000) ;
 y = sin(t) ;

   figure
   hold on
   plot(t,y) ;
   %%get zeros
   tol = 10^-3 ;
   idx = abs(y-0)<=tol ;
   plot(t(idx),y(idx),'*r') ;

   %%using fzero 

   fun = @sin ;
   x = fzero(fun,[0 2*pi]) ;