fzero function with cases

I have to search for the zero of a function that has 2 cases , but it doesn't work

Are there other way to define a function that has cases?

e = 0.1;                      
zeri=zeros(length(step),1);
i=1;
f=@(e,par) (par==1).*((sqrt(2*mass*e/h2))*sin(sqrt(2*mass*e/h2)*a)-(sqrt(2*mass*(vo-e)/h2))*cos(sqrt(2*mass*e/h2)*a))+(par==2).*((sqrt(2*mass*e/h2))*cos(sqrt(2*mass*e/h2)*a)+(sqrt(2*mass*(vo-e)/h2))*sin(sqrt(2*mass*e/h2)*a));
par = 1;  % ^case 1                                                                                                    ^case 2     
 while   e<vo    
        try y = fzero(f, [e,e+0.1]);                   
            line([-a a],[y y],'Color','red');              
            zeri(i)=y;                                    
             i = i +1
           if par==1
              par=2
           else
              par=1
           end
        end
 end 
  e = e +0.1  

Answer 1

[Star Strider]

The correct way to use ‘f’ with fzero in the posted code is:

y = fzero(@(e)f(e,par), [e,e+0.1]);

There are too many missing variables to be able to run your code (and I have no idea what you are doing with half of a try-catch block).

Also, there may be problems using the limits for fzero, since there may not be a zero-crossing between those values.