impz command from signal package

[Robert Carroll]

Hi,

I’m running Octave-gui v. 4.0.3 on a mac running OS X High Sierra 10.13.6.

I am trying to call the impz command from the signal package. If I run 'pkg list’ I see that I have the package installed.

The command window displays ‘signal * 1.3.2 /Users/rob/octave/signal-1.3.2’.

However, I get error ‘incorrect call to roots’ if I try to call:

pkg load signal;
[z, fs] = impz (x, y);

Both are lines in my .m file. What is the correct way to access this function from the signal package?

thanks

[Sergei Steshenko]

On Friday, November 9, 2018, 11:33:29 PM GMT+2, Robert Carroll <***@bell.net> wrote:

Hi,

I’m running Octave-gui v. 4.0.3 on a mac running OS X High Sierra 10.13.6.

I am trying to call the impz command from the signal package. If I run 'pkg list’ I see that I have the package installed.

The command window displays ‘signal * 1.3.2 /Users/rob/octave/signal-1.3.2’.

However, I get error ‘incorrect call to roots’ if I try to call:

pkg load signal;
[z, fs] = impz (x, y);

Both are lines in my .m file. What is the correct way to access this function from the signal package?

thanks

rob
====================================
The "incorrect call to roots" error message most likely comes from the 'roots' function. If it's the case, then the calling function is at fault. So your "What is the correct way to access this function from the signal package?" may be a wrong question.
According to https://octave.sourceforge.io/signal/function/impz.html 'impz (x, y)' is a legal form of call. So run the function under debugger to see what causes the error message. This might be a bug in the signal package. Or just lack of some input arguments check by 'impz'.
--Sergei.

[Mike Miller]

Post by Robert Carroll
pkg load signal;
[z, fs] = impz (x, y);
Both are lines in my .m file. What is the correct way to access this
function from the signal package?

That looks correct to me. In fact, I am unable to reproduce the error
you are seeing with the same call. Can you share what x and y are? Is it
possible that you have a non-standard 'roots' function in your load
path? Was the error message "incorrect call to roots" or was it

error: Invalid call to roots. Correct usage is:

-- Function File: roots (C)