## Pole Plot of System-vector

### Julian (view profile)

on 28 Apr 2013

I want to plot all due to quantization possible poles of different filter structures (all SOS) and therefore would need following code to run (I don't post the whole code but instead start directly in front of the thing that doesn't work, but I will explain what I did until there):

```% c has 121 rows and 3 columns, it holds 121 denominators with 3 coefficients each
```
```p = pole(tf(1, c));
```

now this line is giving me the error: "The values of the "num" and "den" properties must be row vectors or cell arrays of row vectors, where each vector is nonempty and containing numeric data. Type "ltiprops tf" for more information."

Now I have to admit that I couldn't find something useful about solving this error, and I would really like to avoid something like a for loop where i calculate the poles for each system on its own, because I will have many more system later which leads to awfully slow calculation.

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### Iman Ansari (view profile)

on 28 Apr 2013
Edited by Iman Ansari

### Iman Ansari (view profile)

on 28 Apr 2013

Hi. It's works, but maybe it's not correct:

```c = rand(121,3);
Cell_Den = mat2cell(c,ones(121,1),3)';
Cell_Num(1:121) = {1};
Trans = tf(Cell_Num,Cell_Den);
p = pole(Trans);
p = reshape(p,[2,121]);
```

Julian

### Julian (view profile)

on 28 Apr 2013

thanks for the answer, i'm a little bit short on time right now but i'll try this out tomorrow.