我正在尝试安装angular cli，但显示错误。 错误是
npm ERR! code ENOTFOUND
npm ERR! errno ENOTFOUND
npm ERR! network request to https://registry.npmjs.org/@angular%2fcli failed, reason: getaddrinfo ENOTFOUND proxy.comviva.com proxy.comviva.com:8080
npm ERR! network This is a problem related to network connectivity.
npm ERR! network In most cases you are behind a proxy or have bad network settings.
npm ERR! network
npm ERR! network If you are behind a proxy, please make sure that the
npm ERR! network 'proxy' config is set properly. See: 'npm help config'
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\malaya.choudhury\AppData\Roaming\npm-cache\_logs\2018-12-03T07_09_20_267Z-debug.log
请给我解决方法。