Is there an equivalent function of unit delay in matlab that I can use in M-files?

I would like to write a script M-file to simulate the time delay phenomenon of discrete dynamical system. To hold the feedback control signal at an arbitrary time delay, which is a multiple of sampled time, one can use either the z-1 or z-n module in simulink. Is there equivalent matlab functions that support such function that I can implement in M-files? Thanks in advance.

[ES]

You need this, use a MATLAB Fcn Block and place your code inside.

http://www.mathworks.in/help/simulink/ug/creating-an-example-model-that-uses-a-matlab-function-block.html

Answer 1

[Arkadiy Turevskiy]

Using Control System Toolbox you can specify a delay in your LTI system. You can then simulate the LTI system using commands such as step or lsim.

Example below. More info here.

s=tf('s');
sys_no_delay=1/(s+1);
sys_delay=sys*exp(-1*s); % 1 sec delay
step(sys_no_delay);
hold on;
step(sys_delay,'r');

[Ulfat Hasangarayev]

What is Just sys out there? is that mistake?

[Walter Roberson]

should be sys_no_delay