Re: installation errors

[Mike Miller]

On Tue, Mar 22, 2016 at 11:22:01 +0500, HAMZA ZULFIQAR L1F13BSCS2607 wrote:
> i update my octave in ubuntu from 3.8 to 4.0 and now when i install
> packeges then these errors occur. when i use this command "sudo apt-get
> update" then error occur some of them are
> Err http://ppa.launchpad.net trusty/main amd64
> Packages
>   404  Not Found
> Err http://ppa.launchpad.net trusty/main i386
> Packages
>   404  Not Found
> W: Failed to fetch
> http://ppa.launchpad.net/picaso/octave/ubuntu/dists/trusty/main/binary-amd64/Packages
> 404  Not Found
> 
> W: Failed to fetch
> http://ppa.launchpad.net/picaso/octave/ubuntu/dists/trusty/main/binary-i386/Packages
> 404  Not Found
> 
> E: Some index files failed to download. They have been ignored, or old ones
> used instead.

It looks like you need to fix your apt configuration. That is out of
scope for this mailing list, please use the resources mentioned here:

  http://www.ubuntu.com/support

> warning: the 'rgb2gray' function belongs to the image package from Octave
> Forge
> which seems to not be installed in your system.
> 
> Please read <http://www.octave.org/missing.html> to learn how you can
> contribute missing functionality.
> warning: called from
>     __unimplemented__ at line 524 column 5
> error: 'rgb2gray' undefined near line 1 column 3

If you can figure out how to fix your apt configuration and install the
octave-image package, you should be able to load the image package and
use its functions.

-- 
mike