A lot of people have reported this error message: "
Error: object ‘is.factor.ff’ is not exported by 'namespace:ff'” when trying to run older versions of the OHDSI R packages. This appears to be caused by inconsistencies between the new version of ff and ffbase.
The best solution is to upgrade to the newer OHDSI packages, where we have replaced ff with Andromeda.
However, if you’re stuck with the old packages, here’s how to downgrade ff to solve the problem:
library(devtools) Sys.setenv("R_REMOTES_NO_ERRORS_FROM_WARNINGS"=TRUE) install_version("ff", version = "2.2-14", repos = "http://cran.us.r-project.org")