我正在尝试在新安装的Ubuntu 16.04上安装Octave。所以我尝试了以下命令：
在执行“sudo apt-get update”之后，我遇到了以下错误和警告：
在执行完“sudo apt-get install octave”之后：
在这之后，当我尝试执行 'sudo apt-get -f install' 命令时：
我尝试安装依赖项以便编译源代码，但出现了类似的错误（sudo apt-get install libarpack2）：
现在我能做什么？
sudo apt-add-repository ppa:octave/stable
sudo apt-get update
sudo apt-get install octave
在执行“sudo apt-get update”之后，我遇到了以下错误和警告：
Err:9 http://ppa.launchpad.net/octave/stable/ubuntu xenial/main amd64 Packages
404 Not Found
Err:10 http://ppa.launchpad.net/octave/stable/ubuntu xenial/main i386 Packages
404 Not Found
W: The repository 'http://ppa.launchpad.net/octave/stable/ubuntu xenial Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://ppa.launchpad.net/octave/stable/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/octave/stable/ubuntu/dists/xenial/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
在执行完“sudo apt-get install octave”之后：
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
octave : Depends: libarpack2 (>= 2.1) but it is not going to be installed
Depends: libcholmod3.0.6 but it is not going to be installed
Depends: liboctave3 (= 4.0.0-3ubuntu9) but it is not going to be installed
Depends: libosmesa6 (>= 10.2~) but it is not going to be installed
Recommends: libopenblas-base but it is not going to be installed or
libatlas3-base but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
在这之后，当我尝试执行 'sudo apt-get -f install' 命令时：
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
我尝试安装依赖项以便编译源代码，但出现了类似的错误（sudo apt-get install libarpack2）：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
libarpack2 : Depends: libgfortran3 (>= 4.6) but it is not going to be installed
Depends: liblapack3 but it is not going to be installed or
liblapack.so.3
E: Unable to correct problems, you have held broken packages.
现在我能做什么？
universe仓库中已经有了4.0.0版本 - 你真的需要一个PPA吗？ - steeldriver