Dear Hamidreza,

Thanks for your comments. Some codes unfortunately work only with older versions. I am not sure update always be the best choice.

Dear Mehdi!

You can use the older version of a package, you have to install it from the source.

For example:

packageurl

update.packages("") will update entire library

The problem exists when a new version of R does not support an existing Package. Then you cannot install that Package via CRAN and you probably have to install it via GitHub, if you are lucky and a repository exists.

NOt sure if it's the best way, but i have two different R versions installed in my machine, to make sure the package i need are in the right version.

if you want to stay reproducible and take care of using different versions of R and R packages with different projects, you might take snapshots of R. The package packrat might be a good choice for it.

There has been a report on R-Bloggers considering this topic, see http://www.r-bloggers.com/introducing-the-reproducible-r-toolkit-and-the-checkpoint-package/

This might be interesting for your question

update: http://www.r-bloggers.com/updated-checkpoint-package-faster-reproducibility-with-more-feedback/

Hello Mehdi, from tools options in R studio there is option called general from this you can change the version of R. If you want more control use renv package.