问题：

我在安装一些python库和包，不断得到这个错误，

sudo apt-get install python-scipy 


Reading package lists... Done


Building dependency tree 


Reading state information... Done


Package python-scipy is not available, but is referred to by another package.


This may mean that the package is missing, has been obsoleted, or


is only available from another source



E: Package 'python-scipy' has no installation candidate

答案1：

python 2生命周期已经结束，

你仍然可以通过从18.04 LTS 资料库下载来安装这个包

cd ~/Downloads


wget http://archive.ubuntu.com/ubuntu/pool/universe/p/python-scipy/python-scipy_0.19.1-2ubuntu1_amd64.deb


sudo apt-get install ./python-scipy_0.19.1-2ubuntu1_amd64.deb

答案2：

你想要的软件包是python3-scipy，而不是python-scipy，可以使用以下命令安装它：

apt install python3-scipy

你最好通过scipypip(用于python 2)或pip3 来安装，

 
pip install scipy

或者

 
pip3 install scipy

详情请查看man pip3。