Control systems package for GNU Octave

[johnathanmcclure]

I was using GNU Octave today to follow some MATLAB examples given in my university course on control systems.

One of the examples was to input a basic transfer function. When I tried to type in:


num1=[10]; den1=[1 2 5]; sys1=tf(num1, den1)An error was returned:

error: 'tf' undefined near line # column #I was frustrated because the online manual for Octave seems to clearly describe the "tf" function. Why was the tf function missing?

After searching for a while, I found this mailing list posting (https://www-old.cae.wisc.edu/pipermail/help-octave/2009-October/016389.html), where I discovered the stock installation of Octave in the Ubuntu repositories does not include control system functions.

To get these functions, you have to download and install them from Octave-Forge (http://octave.sourceforge.net/). There are a number of add-on packages available that are not in the default install.

In this case, I wanted the Controls packge, which is at http://octave.sourceforge.net/control/index.html.

Once I had the .tar.gz I went to the command line and did

$ sudo octave
octave:1> pkg install /foo/bar/downloadedpackage.tar.gz
The results using Octave as a direct replacement for MATLAB aren't perfect, but it's going much better with the Control package!

[not_a_phd]

Did you try to get them through the Ubuntu repositories first?

I think that the octave-control package is what you were looking for.

[johnathanmcclure]

Did you try to get them through the Ubuntu repositories first?

I think that the octave-control package is what you were looking for.

I think I tried to apt-get octave-control. It didn't work on my 8.04 rig or my upgraded 9.10 64bit rig.

You seem to be right, it is in the repositories for 9.10, so I don't know what went on with my PC. And it's also a package for 9.04, so those are theoretically covered too. But it's not a package under 8.04 or 8.10, hmmm.

At least the workaround I describe seems to work on my rigs running 8.04 and 9.10. I guess before trying it it'd be a good idea to attempt


sudo apt-get install octave-control

[NibblerSA]

Thanks for the help!