z transform of a sequence

Hi,

i need to find the z transform of a sequence. ztrans in matlab does it for symbolic input. but i need to find it for a sequence like [1 2 3 4].

please help. thanks in advance

-saima

[manoj joshi]

https://www.youtube.com/watch?v=lpBhat9mVho

watch this video for find finding z transform of discrete signal without using function in matlab

[Anju K]

Respected madam,

I have already written the the MATLAB program code to find the Z transform of a finite duration sequence, in my blog at http://s5electronicsandcommunication.blogspot.com/2012/12/matlab-program-for-z-transform.html . Please read it and please tell your valuable opinion about it.

Anju K

Answer 1

[Wayne King]

The vector you give has a finite number of terms so the Z transform is just

1+2z^{-1}+3z^{-2}+4z^{-3}

unless the terms you give do not correspond to those powers of z. If they don't then we need to know which powers of z they do correspond to.

For example, is this a Laurent polynomial with both negative and positive powers of z?

Answer 2

[Shakeel Ahmad Waqas]

How will I find Z transform of a System using same approach. e.g. I want to find z Transform of a system y[n]-2y[n-1]-3y[n-2]=x[n]-2x[n-1]+3x[n-2]; Can you please help me in this.?

Answer 3

[Anirudh Roy]

First create a 'Z Transform Variable'

Z=tf('Z')

Then say your array is A, and the Z transform is B

for n=1:length(A)
    B=B+A(n)*Z^-n; % Assuming B=0 initially 
end

Hope it helps

Answer 4

[Harsha Vardhan Rao Avunoori]

Hello Saima,

I am assuming that the sequence which you have are the coefficients of a polynomial say

y = 1 + 2x+ 3x^2+4x^3

and you want to compute Y(z).

I followed this procedure to get the ztrans.

syms n;
 f =   1 + 2*(n) + 3*(x^2) + 4*(x^3);
 ztrans(f)

Let me know if you were expecting a similar approach like this.

-Harsha

[vikash]

sorry but i need a help! how to write it if the sequence is big, say 500 elements

[Walter Roberson]

Use poly2sym() to construct a polynomial in a single variable with given coefficients.

Answer 5

[abid khan]

Hi,

I want to calculate the ztransform of x(n)=[1 2 3 4]in matlab plz reply if any know

Thanks

Abid

[Naveed Ahmed]

You can look at the reply of Wayne King. The Z-transform of this sequence is the same

Answer 6

[Leonora Brati]

Furious discrete time transformation of DTFT signal using as tool

DFT calculation, hence X (𝑒𝑗𝜔).

5.75*(1/3)^n*u(n)-10.18*(1/4)^n*u(n)-[(-1)^(n-3)-(-3)^(n-3)]*u(n-3)+(3/2)*(-3)^(n-5)*u(n-5) z transform

[Walter Roberson]

Unfortunately, I do not understand what you are trying to convey here??

Answer 7

[shuma benti]

are auto correlation are commutative

Answer 8

[Sundeep Javvaji]

If y is your input sequence,

bode_y = 0;
for n = 1:length(y)
    bode_y = bode_y + y(n)*tf([1],[1 zeros(1,n-1)],1);
end