Centos7安装python3、numpy、scipy、matplotlib、pandas等

centos 7 已经自带 python 2.7.15，这里需要安装 python 3

[root@pwm]# python
Python 2.7.15 |Anaconda, Inc.| (default, Dec 14 2018, 19:04:19)
[GCC 7.3.0] on linux2

第一步：安装依赖包

yum -y groupinstall "Development tools"

yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel

第二步：下载python 3，这里下载 3.8.5

https://www.python.org/downloads/source/

用迅雷下载，然后上传

wget https://www.python.org/ftp/python/3.8.19/Python-3.8.19.tar.xz

wget https://www.python.org/ftp/python/3.8.5/Python-3.8.5.tar.xz

第三步：指定存放目录(/usr/local/python3就是python3的安装目录)

mkdir /usr/local/python3

第四步：解压压缩包，进入该目录

yum install libffi-devel -y # 安装 libffi-devel ，这个是为了 _ctypes 模块

tar -xvJf Python-3.8.19.tar.xz
cd Python-3.8.19
./configure --prefix=/usr/local/python3

(注：./configure --prefix=/usr/local/python3这句的作用就是将程序安装在/usr/local/python3这个目录下)

第五步：安装python3

make && make install

(注：make是编译，make install是安装)

第六步：创建软链接(将 /usr/bin/python3指向/usr/local/python3/bin/python3)

ln -s /usr/local/python3/bin/python3 /usr/bin/python3

ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3

检查pip和pip3对应的python的版本，如果是3.6，需要删除，然后重新建立 link

[root@VM-8-12-centos ~]# which pip3
/usr/local/bin/pip3
[root@VM-8-12-centos ~]# /usr/local/bin/pip3 -V
pip 21.3.1 from /usr/local/lib/python3.6/site-packages/pip (python 3.6)
[root@VM-8-12-centos ~]# /usr/local/python3/bin/pip3 -V
pip 23.0.1 from /usr/local/python3/lib/python3.8/site-packages/pip (python 3.8)

rm /usr/bin/pip3

rm /usr/local/bin/pip3
ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3

which pip
/usr/local/bin/pip
rm /usr/local/bin/pip

ln -s /usr/local/python3/bin/pip3 /usr/local/bin/pip

pip -V

升级pip(如果需要)

按照提示升级pip，命令：pip3 install --upgrade pip

使用：

/usr/local/python3/bin/python3

修改系统默认的python2.7为python3

which python
/usr/bin/python

sudo rm /usr/bin/python
sudo ln -s /usr/local/python3/bin/python3 /usr/bin/python

==========================================

[root@VM-8-12-centos backend]# locate pip3
/usr/bin/pip3
/usr/bin/pip3.6
/usr/local/python3/bin/pip3
/usr/local/python3/bin/pip3.8
/usr/local/qcloud/python/bin/pip3
/usr/local/qcloud/python/bin/pip3.7
/usr/share/bash-completion/completions/pip3
/usr/share/bash-completion/completions/pip3.6

[root@VM-8-12-centos backend]# ll /usr/bin/ | grep pip
-rwxr-xr-x.   1 root root        2291 Jul 31 2015 lesspipe.sh
lrwxrwxrwx    1 root root           9 Jan 8 2021 pip-3 -> ./pip-3.6
lrwxrwxrwx    1 root root           8 Jan 8 2021 pip-3.6 -> ./pip3.6
-rwxr-xr-x    1 root root         407 Oct 14 2020 pip3.6

[root@VM-8-12-centos backend]# ll /usr/local/python3/bin/ | grep pip
-rwxr-xr-x 1 root root 237 Aug 27 20:19 pip3
-rwxr-xr-x 1 root root 237 Aug 27 20:19 pip3.8

/usr/local/python3/bin/pip3 -V
pip 23.0.1 from /usr/local/python3/lib/python3.8/site-packages/pip (python 3.8)