using hold on function in step response with subplot

I am trying to plot step reponse and impulse reponse of a sys in a single plot,using suplot and lengend, but i too have different values of z to be ploted (means i am using hold on fun). when i try to use subplot with the created code it's plotting for only one value of z, but i want such that all the three values of z has to plotted for both the step and impulse function in subplot, I apperciate your help.

s=tf('s');
z=[3 6 12];
hold on
for i=1:3
    zc=z(i);
    g=(15/zc)*((s+zc)/(s^2+3*s+15));
    subplot(2,1,1)
    step(g)
    subplot(2,1,2)
    impulse(g)
end
legend('z = 3','z = 6','z = 12')            

Answer 1

[Walter Roberson]

Code attached. Mostly it was moving the hold()

[BALA GUGA GOPAL S]

Thank you for your help, It got worked with your method.

Answer 2

[GMD Baloch]

You just have to a little bit of modification in your code. I have done it and it is producing the following result

I hope that you wanted the above output. The modified code is given below

s=tf('s');
z=[3 6 12];
for i=1:3
    zc=z(i);
    g=(15/zc)*((s+zc)/(s^2+3*s+15));
    subplot(2,2,i)
    step(g)
    hold on
    impulse(g)
    legend('z = 3','z = 6')
end

[BALA GUGA GOPAL S]

Thank for your help. but when i try to plot for all the values of z(i) in single plot only values for z=3,6 is being only plotted.for both impulse and step. But i want something like this combined in a single plot using subplots for step and impulse. I apperciate your help in regard this.

[GMD Baloch]

Do you want step response for z = 3,6 and 12 in one subplot and impulse response for z = 3,6 and 12 in another subplot?

[BALA GUGA GOPAL S]

Yes sir, the exact way you asked for, step response for z = 3,6 and 12 in one subplot and impulse response for z = 3,6 and 12 in another subplot. any help with that in the above code will be helpfull, i have tried lot ways.

[BALA GUGA GOPAL S]

Thank you with little bit more of change in the code you gave it, it worked. Answer script is given by Mr.Walter attached down. Thank for your help

[GMD Baloch]

You can try the following code

s=tf('s');
z=[3 6 12];
subplot(2,1,1)
hold on
for i=1:3
    zc=z(i);
    g=(15/zc)*((s+zc)/(s^2+3*s+15));
    step(g)
end
legend('z = 3','z = 6','z = 12')
subplot(2,1,2)
hold on
for i=1:3
    zc=z(i);
    g=(15/zc)*((s+zc)/(s^2+3*s+15));
    impulse(g)
end
legend('z = 3','z = 6','z = 12')

The output for this code is shown below

[BALA GUGA GOPAL S]

thank you this too got worked out.Thank you for your help.