In my case, the installation of nlme
package is in trouble:
mv: cannot move '/home/guanshim/R/x86_64-pc-linux-gnu-library/3.4/nlme'
to '/home/guanshim/R/x86_64-pc-linux-gnu-library/3.4/00LOCK-nlme/nlme':
Permission denied
Using Ubuntu 18.04, CTRL+ALT+T to open a terminal window:
sudo R
install.packages('nlme')
q()