Inverse Z-Transform of z/(z-a) - Strange result

Hello everyone, I tried to get the inverse Z-transform of z/(z-a) with the following lines:

close all
clear all
syms a n z
iz=iztrans(z/(z-a),z,n)

the result is:

piecewise([a == 0, kroneckerDelta(n, 0)], [a ~= 0, a*(a^n/a - kroneckerDelta(n, 0)/a) + kroneckerDelta(n, 0)])

but I expect a^n. How can I get a^n?

Thank you for your time.

[Karan Gill]

To add to Star Strider's answer below, your result contains the piecewise function. See that doc page for more info.

Answer 1

[Star Strider]

Specify ‘a>0’, and simplify:

syms a n z
assume(a > 0)
iz=iztrans(z/(z-a),z,n);
iz = simplify(iz);

iz =
a^n

[fadli yusuf]

thanks

Answer 2

[Arthur Ngnepiepaye]

Can someone help me out plotting this zero input response? It's confusing

[Star Strider]

Post this as a new Question.