What does "sys.which" function not found error mean in RStudio?

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The "sys.which" function is not a built-in function in base R, so if you are getting a "function not found" error for this function in RStudio, it means that the required package that contains this function is not loaded or not installed.

You can install and load the required package that contains the "sys.which" function using the following command:

install.packages("sys")

library(sys)