1 Save, Load, and Quit R Sessions or Workspaces

To save all objects in your workspace for the current session to the working directory, use:

save.image("filename.RData")

For example:

save.image("homework.RData")

Or save to a specific location:

# Windows
save.image("C:/Users/Public/Statscodes/Rdata/files/filename.RData")
# macOS
save.image("/Users/Public/Statscodes/Rdata/files/filename.RData")

Alternatively, to save only certain objects, use:

save(hmw_data, output_table, file = "filename.RData") # List as many objects as you want.

To load the objects saved from a workspace in an earlier session from the working directory, use:

load("filename.RData")

Or from a specific location:

# Windows
load("C:/Users/Public/Statscodes/Rdata/files/filename.RData")
# macOS
load("/Users/Public/Statscodes/Rdata/files/filename.RData")

To quit your R session, use:

q()

Or:

quit()

2 See List and Structure of Objects, and Remove Objects in R

To see list of objects in your environment, use:

ls()

To see the structure of a specific object, use:

str(object)

For example:

str(BOD)

'data.frame':   6 obs. of  2 variables:
 $ Time  : num  1 2 3 4 5 7
 $ demand: num  8.3 10.3 19 16 15.6 19.8
 - attr(*, "reference")= chr "A1.4, p. 270"

To see the structure of all objects in your environment, use:

ls.str()

To remove specific objects, use:

rm(hmw_data, output_table) # List as many objects as you want.

To remove all objects in your environment, use:

rm(list = ls())

3 Save, Load, Display, and Clear Commands List in R

To save all commands in your session, use:

savehistory(".Rhistory")

If saved as above with no filename and to the default working directory, your commands list will be automatically loaded each time you launch R.

Or specify a filename, which will not be automatically loaded:

savehistory("filename.Rhistory")

# Or to specific locations
# Windows
savehistory("C:/Users/Public/Statscodes/Rdata/files/homework.Rhistory")
# macOS
savehistory("/Users/Public/Statscodes/Rdata/files/homework.Rhistory")

To load commands list from an earlier session, use:

loadhistory("filename.Rhistory")

# Or from specific locations
# Windows
loadhistory("C:/Users/Public/Statscodes/Rdata/files/homework.Rhistory")
# macOS
loadhistory("/Users/Public/Statscodes/Rdata/files/homework.Rhistory")

To display all commands in your session, use:

history(max.show = Inf)

Or for limited number of commands, for example, the 10 most recent (default = 25), use:

history(max.show = 10)

Or for the default size, which is the 25 most recent, use:

history()

To clear commands and results from your console, use:

CTRL + L. Note that you can still access the commands with the "up arrow" (\(\uparrow\)) on your keyboard and objects are still available.