今天使用pip3安装numpy时居然给我安装到了home下的.local/lib/python3.5/dist-packages目录，有点恼火，按到这里也是能使用的，但不方便管理呀，不明所以，这pip3咋不安装到/usr/local/lib/python3.5/dist-packages啦？
怀疑是pip3命令问题，使用find / -name pip3我找到了pip3命令启动位置，查看了一下，pip3命令中调用了pip命令，而home下的。cache目录下居然有pip文件夹，进过实验确实是这样的，不过还不明白这到底是怎么回事
百思不得其解，在网上也找了好久没看到，最后试了下安装命令前加个sudo居然解决了这个问题。
而且在加上sudo 后出现下面一些警示语句：
sudo pip3 install numpy
The directory '/home/ddyy/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/ddyy/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
不明白这些是说啥，但问题确实解决了