error running sys=tf()

Hi,

i wa having trouble running sys=tf() resulting in an error and the line the code is in displaying in my command window. My code is below. Could you help me?

Y=10;

U= [1,3,10];

sys= tf(Y,U);

[y,t]=impulse(sys,5);

plot(t,y);

xlabel('Time (s)');

ylabel('Amplitude');

title('Problem 3');

grid on;

command window

Error in prob3 (line 3)

sys= tf(Y,U);

Resolved:

Apparently I didn't have the controls toolbox downloaded.

[Dave B]

This seems to run okay to me, is it possible that you have a tf variable defined? Or maybe a different tf function on your path (which tf should report matlab\toolbox\control\ctrlmodels)? clear all might be helpful. Or maybe you don't have this toolbox? I don't see what the error is, did MATLAB not give a little more info?

Y=10;
U= [1,3,10];
sys= tf(Y,U);
[y,t]=impulse(sys,5);
plot(t,y);
xlabel('Time (s)');
ylabel('Amplitude');
title('Problem 3');
grid on;

[Kevin Puertas]

You're right, so apparently i didn't have the controls toolbox.Thanks