how to clean file cached from centos code example

Example: clear cache yum centos 7

#To clean all cached packages from the enabled repository cache directory
yum clean packages

#To purge the old package information completely
yum clean headers

#To clean any cached xml metadata from any enabled repository,
yum clean metadata

#To clean all the cached files from any enabled repository at once,
yum clean all

#change yum file settings
nano /etc/yum.conf
http_caching=none