-Bash: miio: command not found

[HF1643]

The system is CentOS 7,
[root@localhost miio]# sudo miio discover
sudo: miio：找不到命令
[root@localhost miio]# miio --version
-bash: miio: 未找到命令
[root@localhost miio]# miio discover
-bash: miio: 未找到命令

[HF1643]

[root@localhost miio]# npm install miio
npm WARN saveError ENOENT: no such file or directory, open '/root/package.json'
npm WARN enoent ENOENT: no such file or directory, open '/root/package.json'
npm WARN root No description
npm WARN root No repository field.
npm WARN root No README data
npm WARN root No license field.

• miio@0.15.6
  updated 1 package in 2.242s
  [root@localhost miio]# npm install -g miio
  /usr/local/node/node-v8.11.2-linux-x64/bin/miio -> /usr/local/node/node-v8.11.2-linux-x64/lib/node_modules/miio/cli/index.js
• miio@0.15.6
  updated 1 package in 5.488s
  [root@localhost miio]# miio discover
  -bash: miio: 未找到命令
  [root@localhost miio]#