Default Arguments (Functions)

The following function estimates the mass of an organism in kg based on its length in meters and a set of parameter values. For some types of dinosaurs we don’t have specific values of a and b, so we have to use general values that can be applied to a number of different species.

get_mass_from_length_theropoda <- function(length, a, b){
  mass <- a * length ^ b
  return(mass)
}

Rewrite this function so that its arguments have default values of a = 39.9 and b = 2.6 (the average values from Seebacher 2001).

1. Use this function to estimate the mass of a Sauropoda (a = 214.44, b = 1.46) that is 22 m long (by setting a and b when calling the function).
2. Use this function to estimate the mass of a dinosaur from an unknown taxonomic group that is 16m long. Only pass the function length, not a and b, so that the default values are used.