Help with vectorization, instead of loops

I've just recently started reading up on vectorization, and I wondered if anyone could give me some advice on how I could vectorize this code: NB: Instead of the outer while-loop I could've used a for loop from 1:dt:1000, which is why I want to vectorize it. Thanks in advance!!

while t < 1000
    Z = 0.5;
    Kz = (rho*kt*A*pin)/(400*Mh*Gm*fh^2*H*Kh^2);
    fz = Z + log(1-Z) + Kz;
    dfz = 1 - (1/(1-Z));
    while abs(fz/dfz) >= 10^-4
        fz = Z + log(1-Z) + Kz;
        dfz = 1 - (1/(1-Z));
        Z = Z - fz/dfz;
    end %while
    %
    dhdt = @(H) (- (100*Mh)/M *((2*H^2*fh^2*Gm*Z^2)/pin + (kts*As*rho*(H-Hv))/(100*Mh)));
    F1 = dt*dhdt(H);
    F2 = dt*dhdt(H+1/2*F1);
    F3 = dt*dhdt(H+1/2*F2);
    F4 = dt*dhdt(H+F3);
    X(i) = H;
    tvec(i) = t;
    zvec(i) = Z;
    H = H + 1/6*(F1+2*F2+2*F3+F4);
    t = t + dt;
    i = i + 1;
end %while
plot(tvec,X);
figure
plot(tvec,zvec)