Do variables exist?
If R cannot find a variable in the current environment, it will look in the parent environment, then the grandparent environment, and so on until it finds it.
rsa_env has been modified so it includes capitals and national_parks, but not population.
Deze oefening maakt deel uit van de cursus
Introduction to Writing Functions in R
Oefeninstructies
- Check if
populationexists inrsa_env, using default inheritance rules. - Check if
populationexists inrsa_env, ignoring inheritance.
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Compare the contents of the global environment and rsa_env
ls.str(globalenv())
ls.str(rsa_env)
# Does population exist in rsa_env?
___("___", envir = ___)
# Does population exist in rsa_env, ignoring inheritance?
___