% function to count zeros of f  between a and b
% This code is rough; it assumes that a and b are % not zeros, and the none of the chose points 
% are zeros.  It should be modified to  allow
% fof these posibilities

function count=find_zeros(f,a,b)
    N=10000000;
    x=[a:1/N:b];
    count=0;
    for k=2:N
        if f(x(k))*f(x(k-1))<0
            count=count+1;
        end
    end      
return
