Frobenius norm of a null matrix is not zero

[Ben Abbott]

On Jan 14, 2008, at 5:37 AM, Rolf Fabian wrote:

>
> You should not expect that anybody doing work for Octave is
> doing it always on a UNIX system.
>
> E.g. trying to use 'diff.exe' (which is distributed as part of
> 'msys' shell with the Octave 3.0.0 windows installer) from
> within a Windows XP command prompt ('cmd') results in :
>
>   Microsoft Windows XP [Version 5.1.2600]
>   (C) Copyright 1985-2001 Microsoft Corp.
>
>   C:\WINDOWS\system32> diff --help
>   'diff' is not recognized as an internal or external command,
>   operable program or batch file.
>
> Obviously appropriate system paths for 'msys' were not added
> during the installation process ( at least on the system I used ).
>
> I needed some time to figure out, that in order to use 'diff'
> implemented in the Windows 'msys' - shell is expected to be
> used from the Octave prompt using Octave's "system"-command
> ( then 'msys'-functions are obviously found ):
>
> octave-3.0.0.exe:1>
> system ("diff  -u  old_file.m  new_file.m  >  new_file.patch")
>
> which is a bit different from your oversimplification above.
>
> Rolf Fabian
>
>
>
> John W. Eaton wrote:
>>
>> On 11-Jan-2008, Rolf Fabian wrote:
>>
>> |
>> | This fixes the problem.
>> | Sorry, no time to send patches etc ....
>>
>> Sorry, how hard is it to run diff -u my-orig-file my-new-file?
>>
>> jwe
>>
> -----
> Rolf Fabian
> <r dot fabian at jacobs-university dot de>


Rolf,

It appears to me that the changes you made and those of jfc were  
different (at least a diff of yours produced a larger result).

Are jfc's in fact the same, or sufficient?

Ben