Re: Problems with control package

[Lukas Reichlin]

On 14.12.2013, at 09:59, David Collins <address@hidden> wrote:

> Hi. I have recently upgraded my installation of the control package to the 
> latest version on Octave Forge, but have run into problems.
> 
> I'm running Octave 3.6.2 on on Debian Wheezy.
> I have removed the Debian octave-control package, and installed the latest 
> version using
> octave:1> pkg install -forge control;
> 
> This seemed to succeed without errors.
> octave:1> pkg describe control
> ---
> Package name:
>        control
> Version:
>        2.6.1
> Short description:
>        Computer-Aided Control System Design (CACSD) Tools for GNU Octave, 
> based on the proven SLICOT Library
> Status:
>        Loaded
> 
> 
> However, when I try command such as 'arx()' or 'iddata()' I get the following 
> errors:
> 
> octave:5> dat = iddata(Y,U);
> error: __experiment_dim__: 
> /usr/lib/i386-linux-gnu/octave/packages/control-2.6.1/i486-pc-linux-gnu-api-v48+/is_matrix.oct:
>  failed to load: 
> /usr/lib/i386-linux-gnu/octave/packages/control-2.6.1/i486-pc-linux-gnu-api-v48+/is_matrix.oct:
>  undefined symbol: _ZN3MPI8Datatype4FreeEv
> error: called from:
> error:   /usr/share/octave/packages/control-2.6.1/__iddata_dim__.m at line 
> 50, column 3
> error:   /usr/share/octave/packages/control-2.6.1/__iddata_dim__.m at line 
> 29, column 9
> error:   /usr/share/octave/packages/control-2.6.1/@iddata/iddata.m at line 
> 124, column 14
> 
> 
>> c++filt _ZN3MPI8Datatype4FreeEv
> MPI::Datatype::Free()
> 
> 
> Another problem is that, although 'help @lti/c2d' works as expected, the 
> function itself is unrecognised.
> 
> octave:6> @lti/c2d;
> error: `c2d' undefined near line 6 column 6
> octave:7> c2d;
> error: `c2d' undefined near line 7 column 1
> 
> 
> I'll try to look into this myself, but if anyone has any pointers they are 
> welcome.
> The reason I upgraded the control package was to avail of the 'arx()', 
> 'c2d()' commands, etc..
> 
> David

Hi David

In order to use a function like "c2d" inside the class folder "@lti", at least 
one argument must be of type "lti". "c2d (ss)" should work as expected.
Regarding the MPI error, I'm afraid I can't help.

Lukas